Rename TEST_MODE to specific variable for CodeQL Action

This allows us to set it automatically in the workflow generator,
simplifying things and reducing the scope for error.

.github/workflows/expected-queries-runs.yml

@@ -17,6 +17,8 @@ on:
 jobs:
   expected-queries:
     name: Expected Queries Tests
+    env:
+      CODEQL_ACTION_TEST_MODE: true
     timeout-minutes: 45
     runs-on: ubuntu-latest
     steps:
@@ -31,15 +33,11 @@ jobs:
       with:
         languages: javascript
         tools: ${{ steps.prepare-test.outputs.tools-url }}
-      env:
-        TEST_MODE: true
     - uses: ./../action/analyze
       with:
         output: ${{ runner.temp }}/results
         upload-database: false
         upload: false
-      env:
-        TEST_MODE: true
 
     - name: Check Sarif
       uses: ./../action/.github/check-sarif