Actions: Fix failing Runner autobuild test on macOS

Add the missing `$CODEQL_RUNNER` prefix to the autobuild command line.
This intermediate process works around System Integrity Protection,
allowing the tracer to start the C# extractor for the dotnet builds
within the autobuild process.

The test used to pass without this because the legacy CLR tracer bypassed SIP
while dotnet 5 was used on the Actions virtual environment.
Now that the virtual environment uses dotnet 6, the CLR tracer no longer works,
and we need to explicitly work around SIP.

This test will eventually be replaced by an internal integration test for the
equivalent functionality in the CLI. For now, this change makes the test
continue to pass.

.github/workflows/pr-checks.yml

@@ -414,7 +414,7 @@ jobs:
       - name: Build code
         shell: bash
         run: |
-          ../action/runner/dist/codeql-runner-macos autobuild
+          $CODEQL_RUNNER ../action/runner/dist/codeql-runner-macos autobuild
 
       - name: Run analyze
         run: |