[release/5.0-preview3] Don't run Code Check in official builds

.azure/pipelines/ci.yml

@@ -92,6 +92,7 @@ stages:
   displayName: Build
   jobs:
   # Code check
+  - ${{ if or(eq(variables['System.TeamProject'], 'public'), in(variables['Build.Reason'], 'PullRequest')) }}:
     - template: jobs/default-build.yml
       parameters:
         jobName: Code_check
@@ -594,7 +595,7 @@ stages:
     parameters:
       condition: ne(variables['SkipTests'], 'true')
       jobName: MacOS_Test
-      jobDisplayName: "Test: macOS 10.13"
+      jobDisplayName: "Test: macOS 10.14"
       agentOs: macOS
       isTestingJob: true
       buildArgs: --all --test "/p:RunTemplateTests=false /p:SkipHelixReadyTests=true" $(_InternalRuntimeDownloadArgs)