Install both latest public and latest stable SDKs. Check that solution(s) build with both. (#11988)

* Install both latest public and latest stable SDKs. Check that solution(s) build with both.

azure-pipelines.yml

@@ -386,10 +386,9 @@ stages:
               packageType: sdk
               useGlobalJson: true
               includePreviewVersions: true
-              workingDirectory: $(Build.SourcesDirectory)/service
+              workingDirectory: $(Build.SourcesDirectory)
               installationPath: $(Agent.ToolsDirectory)/dotnet
-          - script: dotnet build ..\FSharp.sln /bl:\"artifacts/log/$(_BuildConfig)/RegularBuild.binlog\"
-            workingDirectory: $(Build.SourcesDirectory)/service
+          - script: dotnet build .\FSharp.sln /bl:\"artifacts/log/$(_BuildConfig)/RegularBuild.binlog\"
             env:
               DOTNET_ROLL_FORWARD_TO_PRERELEASE: 1
             displayName: Regular rebuild of FSharp.sln
@@ -419,10 +418,9 @@ stages:
               packageType: sdk
               useGlobalJson: true
               includePreviewVersions: true
-              workingDirectory: $(Build.SourcesDirectory)/service
+              workingDirectory: $(Build.SourcesDirectory)
               installationPath: $(Agent.ToolsDirectory)/dotnet
-          - script: dotnet build ../FSharp.sln /bl:\"artifacts/log/$(_BuildConfig)/RegularBuild.binlog\"
-            workingDirectory: $(Build.SourcesDirectory)/service
+          - script: dotnet build ./FSharp.sln /bl:\"artifacts/log/$(_BuildConfig)/RegularBuild.binlog\"
             env:
               DOTNET_ROLL_FORWARD_TO_PRERELEASE: 1
             displayName: Regular rebuild of FSharp.sln
@@ -452,10 +450,9 @@ stages:
               packageType: sdk
               useGlobalJson: true
               includePreviewVersions: true
-              workingDirectory: $(Build.SourcesDirectory)/service
+              workingDirectory: $(Build.SourcesDirectory)
               installationPath: $(Agent.ToolsDirectory)/dotnet
-          - script: dotnet build ../FSharp.sln /bl:\"artifacts/log/$(_BuildConfig)/RegularBuild.binlog\"
-            workingDirectory: $(Build.SourcesDirectory)/service
+          - script: dotnet build ./FSharp.sln /bl:\"artifacts/log/$(_BuildConfig)/RegularBuild.binlog\"
             env:
               DOTNET_ROLL_FORWARD_TO_PRERELEASE: 1
             displayName: Regular rebuild of FSharp.sln

global.json

 {
   "sdk": {
-    "version": "6.0.100-rc.1.21379.2",
+    "version": "6.0.100-preview.7.21379.14",
     "allowPrerelease": true,
     "rollForward": "minor"
   },
   "tools": {
-    "dotnet": "6.0.100-rc.1.21379.2",
+    "dotnet": "6.0.100-preview.7.21379.14",
     "vs": {
       "version": "16.8",
       "components": [