Adding code scanning

Author: tpeczek

.github/workflows/codeql.yml

@@ -0,0 +1,46 @@
+name: "CodeQL"
+on:
+  push:
+    branches:
+      - main
+    paths-ignore:
+      - 'Benchmark.AspNetCore.ServerSentEvents/**'
+      - 'DocFx.AspNetCore.ServerSentEvents/**'
+      - 'Test.AspNetCore.ServerSentEvents/**'
+      - '*.md'
+  pull_request:
+    branches:
+      - main
+    paths-ignore:
+      - 'Benchmark.AspNetCore.ServerSentEvents/**'
+      - 'DocFx.AspNetCore.ServerSentEvents/**'
+      - 'Test.AspNetCore.ServerSentEvents/**'
+      - '*.md'
+  schedule:
+    - cron: '00 20 * * 5'
+  workflow_dispatch:
+jobs:
+  analyze:
+    name: Analyze
+    runs-on: windows-latest
+    permissions:
+      actions: read
+      contents: read
+      security-events: write
+    strategy:
+      fail-fast: false
+      matrix:
+        language: [ 'csharp' ]
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v3
+    - name: Initialize CodeQL
+      uses: github/codeql-action/init@v2
+      with:
+        languages: ${{ matrix.language }}
+    - name: Autobuild CodeQL
+      uses: github/codeql-action/autobuild@v2
+    - name: Analyze CodeQL
+      uses: github/codeql-action/analyze@v2
+      with:
+        category: "/language:${{matrix.language}}"