Added Blocks addCustomPostType deprecation notice (#56)

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number below -->
Closes # DR-412

## 💸 TL;DR
Blocks `addCustomPostType` is being deprecated. This PR adds notices for
this.

## 📜 Details
[Design Doc](<!-- insert Google Doc link here if applicable -->)


[Jira](https://reddit.atlassian.net/issues?filter=-1&selectedIssue=DR-412)

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screenshots, external dependency changes -->

## 🧪 Testing Steps / Validation
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and screenshots where applicable -->

## ✅ Checks
<!-- Make sure your pr passes the CI checks and do check the following
fields as needed - -->
- [ ] CI tests (if present) are passing
- [ ] Adheres to code style for repo
- [ ] Contributor License Agreement (CLA) completed if not a Reddit
employee

Author: vdikransamarjian

docs/api/public-api/classes/Devvit.md

@@ -22,6 +22,10 @@
 
 ### addCustomPostType()
 
+:::warning Deprecation notice
+`addCustomPostType` is deprecated and will be unsupported. It will not work after June 30.
+:::
+
 > `static` **addCustomPostType**(`customPostType`): `void`
 
 Add a custom post type for your app.
@@ -43,6 +47,7 @@ The custom post type to add.
 ```ts
 import { Devvit, useState } from '@devvit/public-api';
 
+// addCustomPostType() is deprecated and will be unsupported. It will not work after June 30.
 Devvit.addCustomPostType({
   name: 'Counter',
   description: 'A simple click counter post.',

docs/blocks/button.mdx

@@ -163,6 +163,7 @@ A button that increments a counter
 ```tsx
 import { Devvit, useState } from '@devvit/public-api';
 
+// addCustomPostType() is deprecated and will be unsupported. It will not work after June 30.
 Devvit.addCustomPostType({
   name: 'Say Hello',
   render: (context) => {

docs/blocks/image.mdx

@@ -183,6 +183,7 @@ A button that increments a counter
 ```tsx
 import { Devvit, useState } from '@devvit/public-api';
 
+// addCustomPostType() is deprecated and will be unsupported. It will not work after June 30.
 Devvit.addCustomPostType({
   name: 'Say Hello',
   render: (context) => {

docs/capabilities/blocks/app_image_assets.md

@@ -65,6 +65,7 @@ const render: Devvit.CustomPostComponent = () => {
   );
 };
 
+// addCustomPostType() is deprecated and will be unsupported. It will not work after June 30.
 Devvit.addCustomPostType({
   name: 'My custom post',
   description: 'Test custom post for showing a custom asset!',

docs/capabilities/blocks/dimensions.md

@@ -15,6 +15,10 @@ You can use dimensions to:
 
 ## Getting dimensions
 
+:::warning Deprecation notice
+`addCustomPostType` is deprecated and will be unsupported. It will not work after June 30.
+:::
+
 Dimension information is specified in density-independent pixels. These pixel units are located on the context object.
 
 | Dimension | Description                                                                                                                                                                |
@@ -28,6 +32,7 @@ Dimension information is specified in density-independent pixels. These pixel un
 This example shows a custom post that specifies dimensions.
 
 ```tsx
+// addCustomPostType() is deprecated and will be unsupported. It will not work after June 30.
 Devvit.addCustomPostType({
   name: 'Dimensions app',
   render: (context) => {
@@ -53,6 +58,7 @@ export const MyHeader: Devvit.BlockComponent = (props, context) => {
   );
 };
 
+// addCustomPostType() is deprecated and will be unsupported. It will not work after June 30.
 Devvit.addCustomPostType({
   name: 'Name',
   render: (_context) => {

docs/capabilities/blocks/working_with_useasync.md

@@ -154,6 +154,7 @@ const App = () => {
 };
 
 //add your custom post
+// addCustomPostType() is deprecated and will be unsupported. It will not work after June 30.
 Devvit.addCustomPostType({
   name: 'AppName',
   description: 'Using useAsync with XKCD API',

docs/capabilities/blocks/working_with_useinterval.md

@@ -59,6 +59,7 @@ function getCurrentTime() {
   return `${hours}:${minutes}:${seconds}`;
 }
 
+// addCustomPostType() is deprecated and will be unsupported. It will not work after June 30.
 Devvit.addCustomPostType({
   name: 'Clock',
   render: (context) => {

docs/capabilities/blocks/working_with_usestate.md

@@ -144,6 +144,7 @@ const CountPage: Devvit.BlockComponent<Props> = ({ navigate, setCount, count },
 };
 
 //add your custom post
+// addCustomPostType() is deprecated and will be unsupported. It will not work after June 30.
 Devvit.addCustomPostType({
   name: 'AppName',
   description: 'Navigate between pages and count!',

docs/capabilities/client/forms.mdx

@@ -77,6 +77,7 @@ A form lets your app ask users to input and submit data. Forms can be defined wi
   import { Devvit, useState, useForm } from '@devvit/public-api';
 
   // Interactive post with form
+  // addCustomPostType() is deprecated and will be unsupported. It will not work after June 30.
   Devvit.addCustomPostType({
     name: 'FormExample',
     render: (context) => {
@@ -1048,6 +1049,7 @@ Below is a collection of common use cases and patterns.
     redditAPI: true,
   });
 
+  // addCustomPostType() is deprecated and will be unsupported. It will not work after June 30.
   Devvit.addCustomPostType({
     name: 'Multi-step Form',
     render: (context) => {

docs/capabilities/client/navigation.mdx

@@ -93,6 +93,7 @@ When linking to Reddit content, the navigation function requires the app account
   });
 
   // Interactive post with navigation
+  // addCustomPostType() is deprecated and will be unsupported. It will not work after June 30.
   Devvit.addCustomPostType({
     name: 'Navigation Post',
     render: (context) => {