WIP #665 - Add changes to YML in order to trigger SonarScanner

The main things going on here in the YML are:
* Adding some env vars for SonarScanner
* Adding the SonarScanner package as a build tool
* Adding before-build/after-test steps to setup/teardown SonarScanner
* Separating the "pack" step from the "build" step
  * Pack moved to before-package which occurs after tests pass
  * See https://www.appveyor.com/docs/build-configuration/#build-pipeline
* Tests run with logging & code-coverage detection
* Test results are added as AppVeyor artifacts

appveyor.yml

@@ -2,6 +2,16 @@ image: Previous Visual Studio 2019
 
 environment:
   nodejs_version: "11"
+  # AppVeyor installs Java on its build agents by default, but it
+  # picks an old version that's not compatible with SonarQube.
+  # This brings it up to date.
+  JAVA_HOME: "C:\\Program Files\\Java\\jdk13"
+  sonarcloud_org_name: elsa-workflows
+  sonarcloud_project_name: elsa-core
+  sonarcloud_api_key:
+    secure: qaE9kOVkGGFM7ZMf3YeliZxDU9udTCy6W5xXHJ9T+tXv5qXPMYlIdR7hyNgxW04A
+  sample_variable:
+    secure: MrPipn2VVHXu68PxZWztGA==
 
 version: 2.0.0-preview6.{build}
 
@@ -35,6 +45,22 @@ install:
 
       cd ..\..\..\..\
 
+      dotnet tool install --global dotnet-sonarscanner
+
+before_build:
+  - cmd: echo "The sample variable is %sample_variable%"
+  - cmd: >-
+      dotnet-sonarscanner begin
+      /k:%sonarcloud_project_name%
+      /v:AppVeyor_build_%version%
+      /o:%sonarcloud_org_name%
+      /s:%APPVEYOR_BUILD_FOLDER%\.SonarQube.Analysis.xml
+      /d:sonar.host.url="https://sonarcloud.io"
+      /d:sonar.login=%sonarcloud_api_key%
+      /d:sonar.cs.xunit.reportsPaths=%APPVEYOR_BUILD_FOLDER%\**\TestResults\TestResults.xml
+      /d:sonar.cs.opencover.reportsPaths=%APPVEYOR_BUILD_FOLDER%\**\TestResults\*\coverage.opencover.xml
+      /d:sonar.branch.name=%APPVEYOR_REPO_BRANCH%
+
 build_script:
   - ps: >-
       cd .\src\dashboards\blazor\ElsaDashboard.Application
@@ -43,14 +69,21 @@ build_script:
 
       cd ..\..\..\..\
       
-      dotnet pack Elsa.sln --include-symbols /p:Version=$env:APPVEYOR_BUILD_VERSION
+      dotnet build
 
 test_script:
-  - ps: dotnet test
+  - ps: dotnet test --collect:"XPlat Code Coverage" --logger:xunit -- DataCollectionRunSettings.DataCollectors.DataCollector.Configuration.Format=opencover
+
+after_test:
+  - cmd: dotnet-sonarscanner end /d:sonar.login=%sonarcloud_api_key%
+
+before_package:
+  - ps: dotnet pack Elsa.sln --include-symbols /p:Version="$env:APPVEYOR_BUILD_VERSION"
 
 artifacts:
   - path: '**/*.nupkg'
     name: Packages
+  - path: '**/TestResults/TestResults.xml'
 
 deploy:
   # Deploy to MyGet on every build (in the appropriate branch)