DOC ONLY: Added a contributor wall of fame to the README (microsoft#3381)

### Motivation and Context

<!-- Thank you for your contribution to the semantic-kernel repo!
Please help reviewers and future users, providing the following
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1. Why is this change required? This is not required; it is optional but
is great for community-building.
2. What problem does it solve? It adds an image of the top 100
contributors to the repo near the bottom of the README. Source of dev
pride. :)
3. What scenario does it contribute to? This encourages contributions
and rewards the top 100 contributors.
  4. If it fixes an open issue, please link to the issue here.  N/A
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1. Why is this change required? This is not required; it is optional but
is great for community-building.
2. What problem does it solve? It adds an image of the top 100
contributors to the repo near the bottom of the README. Source of dev
pride. :)
3. What scenario does it contribute to? This encourages contributions
and rewards the top 100 contributors.
  4. If it fixes an open issue, please link to the issue here.  N/A

### Description

<!-- Describe your changes, the overall approach, the underlying design.
These notes will help understanding how your code works. Thanks! -->

Documentation change only

### Contribution Checklist

<!-- Before submitting this PR, please make sure: -->

- [X] The code builds clean without any errors or warnings
- [X] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [X] All unit tests pass, and I have added new tests where possible
- [X] I didn't break anyone 😄

---------

Co-authored-by: Mark Wallace <[email protected]>
Co-authored-by: Weihan Li <[email protected]>

Author: 3 people

README.md

@@ -165,6 +165,10 @@ To learn more and get started:
 - Attend [regular office hours and SK community events](COMMUNITY.md)
 - Follow the team on our [blog](https://aka.ms/sk/blog)
 
+## Contributor Wall of Fame
+
+[![semantic-kernel contributors](https://contrib.rocks/image?repo=microsoft/semantic-kernel)](https://github.com/microsoft/semantic-kernel/graphs/contributors)
+
 ## Code of Conduct
 
 This project has adopted the