Do not trigger e2e test when a PR is approved (microsoft#676)

### Motivation and Context

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  2. What problem does it solve?
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The e2e test action is still having some issue starting the service. The
action keeps failing and blocking PRs from merging.

### Description

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These notes will help understanding how your code works. Thanks! -->
Do not trigger this action when a PR is approved. 


### Contribution Checklist

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

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

.github/workflows/copilot-test-e2e.yml

@@ -3,15 +3,12 @@ on:
   workflow_dispatch:
   merge_group:
     types: [checks_requested]
-  pull_request_review:
-    types: [submitted]
 
 permissions:
   contents: read
 
 jobs:
   e2e:
-    if: github.event.review.state == 'APPROVED' || github.event_name == 'workflow_dispatch'
     defaults:
       run:
         working-directory: webapp