build: Remove Mac/Linux builds

Re-enable once we've moved to Rust, but for now, just kill cross
platform .Net

Author: qdot

azure-pipelines.yml

@@ -73,41 +73,11 @@ jobs:
         inputs:
           targetPath: '$(Build.ArtifactStagingDirectory)'
           artifactName: 'artifacts-$(buildConfiguration)'
-  - job: "Linux"
-    pool:
-      vmImage: 'ubuntu-16.04'
-    strategy:
-      matrix:
-        Debug:
-          buildConfiguration: Debug
-        Release:
-          buildConfiguration: Release
-    steps:
-      - template: build/dotnet-build.yml
-        parameters:
-          dotNetPublishPlatform: "linux-x64"
-          platform: "linux-x64"
-  - job: MacOS
-    pool:
-      vmImage: 'macos-10.13'
-    strategy:
-      matrix:
-        Debug:
-          buildConfiguration: Debug
-        Release:
-          buildConfiguration: Release
-    steps:
-      - template: build/dotnet-build.yml
-        parameters:
-          dotNetPublishPlatform: "osx-x64"
-          platform: "macos-x64"
   - job: Documentation
     pool:
       vmImage: 'vs2017-win2016'
     dependsOn:
       - Windows
-      - MacOS
-      - Linux
     condition: and(succeeded(), or(eq(variables['Build.SourceBranch'], 'refs/heads/dev'), eq(variables['Build.SourceBranch'], 'refs/heads/master')))
     steps:
       - task: PowerShell@2