Activate GH Actions for this project

AppVeyor is being annoying because of the preinstalled
WebDriver in the path.  So I'm going to build on GH Actions
instead.

Author: craigfowler

.github/workflows/dotnetCi.yml

@@ -0,0 +1,101 @@
+name: .NET CI
+
+on:
+  push:
+    branches: [ "master" ]
+  pull_request:
+    branches: [ "master" ]
+
+jobs:
+
+  # Summary:
+  #
+  # * Installs and configures the environment
+  # * Runs all .NET and JS tests
+  #   * In Debug configuration (.NET tests)
+  #   * WebDriver-based tests use a locally-running Chrome browser ONLY
+  # * Packages test results as build artifacts
+  # * Builds & packs the solution in Release configuration
+  # * Uploads the Release config packages as build artifacts
+
+  build_test_and_pack:
+    name: Build, test & package
+    runs-on: ubuntu-24.04
+    timeout-minutes: 30
+
+    env:
+      VersionSuffix: ci.${{ github.run_number }}
+      Configuration: Debug
+      DotnetVersion: 8.0.x
+      DISPLAY: :99
+    
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      # Install build dependencies
+
+      - name: Add .NET global tools location to PATH
+        run: echo "$HOME/.dotnet/tools" >> "$GITHUB_PATH"
+      - name: Install .NET
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: ${{ env.DotnetVersion }}
+      - name: Install DocFX
+        run: dotnet tool install --global docfx
+      # See https://chromium.googlesource.com/chromium/src/+/main/docs/security/apparmor-userns-restrictions.md
+      - name: Disable AppArmor restrictions so Chrome may run
+        run: echo 0 | sudo tee /proc/sys/kernel/apparmor_restrict_unprivileged_userns
+      - name: Start an Xvfb display so Chrome may run
+        run: Xvfb -ac $DISPLAY -screen 0 1280x1024x16 &        
+
+      # Environment setup pre-build
+
+      - name: Restore .NET packages
+        run: dotnet restore
+
+      # Build and test the solution
+
+      - name: Build the solution
+        run: dotnet build -c ${{ env.Configuration }}
+      - name: Run .NET tests
+        id: dotnet_tests
+        run: dotnet test
+        continue-on-error: true
+
+      # Post-test tasks (artifacts, overall status)
+
+      - name: Gracefully stop Xvfb
+        run: killall Xvfb
+        continue-on-error: true
+      - name: Upload .NET test results artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: NUnit test results
+          path: Tests/*.Tests/**/TestResults.xml
+      - name: Fail the build if any test failures
+        if: steps.dotnet_tests.outcome == 'failure'
+        run: |
+          echo "Failing the build due to test failures"
+          exit 1
+
+      # Build the apps in release mode and publish artifacts
+
+      - name: Clean the solution ahead of building in release config
+        run: dotnet clean
+      - name: Build, in release configuration
+        run: dotnet pack -p:VersionSuffix=$VersionSuffix -o packages
+      - name: Upload build result artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: Build results (NuGet)
+          path: packages/*.nupkg
+      - name: Build docs website
+        run: docfx CSF.Extensions.WebDriver.Docs\docfx.json
+      - name: Upload docs website artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: Docs website
+          path: docs/**/*