Port #3828 to release/6.0

eng/pipelines/common/templates/jobs/ci-code-coverage-job.yml

@@ -33,7 +33,6 @@ parameters:
   # True to upload code coverage results to CodeCov.
   - name: upload
     type: boolean
-    default: true
 
 jobs:
   - job: CodeCoverage

eng/pipelines/dotnet-sqlclient-ci-core.yml

@@ -99,6 +99,25 @@ stages:
             image: ADO-MMS22-CodeCov
             pool: ${{ parameters.defaultPoolName }}
             targetFrameworks: ${{ parameters.codeCovTargetFrameworks }}
+            # We only want to upload coverage results to CodeCov from certain
+            # pipelines.  We use the pipeline name (Build.DefinitionName) to
+            # choose.  This is a predefined variable that is available at
+            # template expansion time, so we can use it to supply a true boolean
+            # value to the upload parameter.
+            #
+            # https://learn.microsoft.com/en-us/azure/devops/pipelines/build/variables?view=azure-devops&tabs=yaml#build-variables-devops-services
+            #
+            # We're choosing to upload from these pipelines only:
+            #
+            # - PR-SqlClient-Project
+            # - CI-SqlClient
+            #
+            # Other pipelines that share this template and use a Project
+            # buildType don't add much, if any, value to the coverage reports.
+            # They have not been configured with suitable CodeCov credentials to
+            # perform the upload.
+            #
+            upload: ${{ or(eq(variables['Build.DefinitionName'], 'PR-SqlClient-Project'), eq(variables['Build.DefinitionName'], 'CI-SqlClient')) }}
 
 # test stages configurations
   # self hosted SQL Server on Windows