Add integration test for retrieval of remote config

https://github.com/github/codeql-action/pull/87#pullrequestreview-439357075

.github/workflows/integration-testing.yml

@@ -124,3 +124,24 @@ jobs:
         sarif_file: rubocop.sarif
       env:
         TEST_MODE: true
+
+  retrieval-of-remote-config:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        # Must fetch at least the immediate parents so that if this is
+        # a pull request then we can checkout the head of the pull request.
+        fetch-depth: 2
+
+    # If this run was triggered by a pull request event then checkout
+    # the head of the pull request instead of the merge commit.
+    - run: git checkout HEAD^2
+      if: ${{ github.event_name == 'pull_request' }}
+
+    - uses: ./init
+      with:
+        languages: javascript
+        config-file: github/codeql-action/.github/codeql/codeql-config.yml@main
+    - uses: ./analyze