[WASM] Pin release branch for integration test

Author: kateinoigakukun

.github/workflows/main.yml

@@ -185,6 +185,7 @@ jobs:
         with:
           repository: swiftwasm/integration-tests
           path: integration-tests
+          ref: release/5.3
       - name: Run integration tests
         run: |
           sudo xcode-select --switch /Applications/Xcode_12.2.app/Contents/Developer/
@@ -232,6 +233,7 @@ jobs:
         with:
           repository: swiftwasm/integration-tests
           path: integration-tests
+          ref: release/5.3
       - name: Run integration tests
         run: swift run # Use TOOLCHAIN env value
         working-directory: ${{ github.workspace }}/integration-tests
@@ -277,6 +279,7 @@ jobs:
         with:
           repository: swiftwasm/integration-tests
           path: integration-tests
+          ref: release/5.3
       - name: Run integration tests
         run: swift run # Use TOOLCHAIN env value
         working-directory: ${{ github.workspace }}/integration-tests