Add e2e test

.github/workflows/e2e-tests.yml

@@ -205,6 +205,27 @@ jobs:
         shell: pwsh
         run: __tests__/verify-dotnet.ps1 -Patterns "^7\.0\.\d+-"
 
+  test-ABCxx-syntax:
+    runs-on: ${{ matrix.operating-system }}
+    strategy:
+      fail-fast: false
+      matrix:
+        operating-system: [ubuntu-latest, windows-latest, macOS-latest]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Clear toolcache
+        shell: pwsh
+        run: __tests__/clear-toolcache.ps1 ${{ runner.os }}
+
+      - name: Setup dotnet 6.0.4xx
+        uses: ./
+        with:
+          dotnet-version: '6.0.4xx'
+      - name: Verify dotnet
+        shell: pwsh
+        run: __tests__/verify-dotnet.ps1 -Patterns "^6\.0\.4\d{2}"
+
   test-dotnet-version-output-during-single-version-installation:
     runs-on: ${{ matrix.operating-system }}
     strategy: