Update all workflows to use Node.js 20 for undici compatibility

Signed-off-by: Gavin Didrichsen <[email protected]>

Author: gavindidrichsen

.github/workflows/mend.yml

@@ -14,10 +14,10 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: 'setup node: 18 platform: ${{ runner.os }}'
+      - name: 'setup node: 20 platform: ${{ runner.os }}'
         uses: actions/setup-node@v4
         with:
-          node-version: 18
+          node-version: 20
 
       - name: npm install
         run: |

.github/workflows/release.yml

@@ -4,7 +4,7 @@ on:
   workflow_dispatch:
 
 env:
-  NODE_VERSION: '18.x'
+  NODE_VERSION: '20'
 
 jobs:
   release:

.github/workflows/release_prep.yml

@@ -16,7 +16,7 @@ jobs:
     name: "Release Prep"
     runs-on: "ubuntu-latest"
     env:
-      NODE_VERSION: "18"
+      NODE_VERSION: "20"
 
     steps:
       - name: "Checkout"