chore(ci): allow external contribution in fast aws tests workflow

.github/workflows/aws_tfhe_fast_tests.yml

@@ -11,16 +11,38 @@ env:
   SLACK_ICON: https://pbs.twimg.com/profile_images/1274014582265298945/OjBKP9kn_400x400.png
   SLACK_USERNAME: ${{ secrets.BOT_USERNAME }}
   SLACK_WEBHOOK: ${{ secrets.SLACK_WEBHOOK }}
-  IS_PULL_REQUEST: ${{ github.event_name == 'pull_request' }}
+  IS_PULL_REQUEST: ${{ github.event_name == 'pull_request' || github.event_name == 'pull_request_target' }}
 
 on:
   # Allows you to run this workflow manually from the Actions tab as an alternative.
   workflow_dispatch:
   pull_request:
+  pull_request_target:
 
 jobs:
+  check-actor-permission:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Get User Permission
+        id: checkAccess
+        uses: actions-cool/check-user-permission@v2
+        with:
+          require: write
+          username: ${{ github.triggering_actor }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Check User Permission
+        if: steps.checkAccess.outputs.require-result == 'false'
+        run: |
+          echo "${{ github.triggering_actor }} does not have permissions on this repo."
+          echo "Current permission level is ${{ steps.checkAccess.outputs.user-permission }}"
+          echo "Job originally triggered by ${{ github.actor }}"
+          exit 1
+
   should-run:
     runs-on: ubuntu-latest
+    needs: check-actor-permission
     permissions:
       pull-requests: write
     outputs:
@@ -55,6 +77,7 @@ jobs:
         with:
           fetch-depth: 0
           token: ${{ secrets.FHE_ACTIONS_TOKEN }}
+          ref: ${{ github.event.pull_request.head.sha }}
 
       - name: Check for file changes
         id: changed-files
@@ -157,6 +180,7 @@ jobs:
         with:
           persist-credentials: 'false'
           token: ${{ secrets.FHE_ACTIONS_TOKEN }}
+          ref: ${{ github.event.pull_request.head.sha }}
 
       - name: Install latest stable
         uses: dtolnay/rust-toolchain@a54c7afa936fefeb4456b2dd8068152669aa8203