Update pipeline generation tool version

Consume latest changes from pipeline generation tool in Azure/azure-sdk-tools#1708

Author: weshaggard

eng/common/pipelines/templates/steps/install-pipeline-generation.yml

@@ -9,7 +9,7 @@ steps:
   - script: >
       dotnet tool install
       Azure.Sdk.Tools.PipelineGenerator
-      --version 1.0.2-dev.20210309.1
+      --version 1.0.2-dev.20210621.1
       --add-source https://pkgs.dev.azure.com/azure-sdk/public/_packaging/azure-sdk/nuget/v3/index.json
       --tool-path ${{parameters.ToolPath}}
     workingDirectory: $(Pipeline.Workspace)/pipeline-generator