ci: delete cache after artifacts upload in canary workflow (#9177)

.github/workflows/canary.yaml

@@ -23,12 +23,14 @@ jobs:
     name: Upload binaries
     needs: build-binaries # run this job after 'build-binaries' job completes
     runs-on: ubuntu-latest
+    env:
+      CACHE_KEY: ${{ runner.os }}-bins-${{ github.workflow }}-${{ github.sha }}
     steps:
       - name: Restore Trivy binaries from cache
         uses: actions/cache@v4
         with:
           path: dist/
-          key: ${{ runner.os }}-bins-${{github.workflow}}-${{github.sha}}
+          key: ${{ env.CACHE_KEY }}
 
         # Upload artifacts
       - name: Upload artifacts (trivy_Linux-64bit)
@@ -58,3 +60,9 @@ jobs:
           name: trivy_macOS-ARM64
           path: dist/trivy_*_macOS-ARM64.tar.gz
           if-no-files-found: error
+
+      - name: Delete cache after upload
+        run: |
+          gh cache delete "$CACHE_KEY" --confirm
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}