Reduce CODEOWNERS for /sdk/template (Azure#2361)

Reduce PR notifications for EngSys tests using azure_template.

Author: heaths

.github/CODEOWNERS

@@ -70,6 +70,7 @@
 /.github/workflows/      @Azure/azure-sdk-eng
 /.github/CODEOWNERS      @RickWinter @ronniegeraghty @Azure/azure-sdk-eng
 /.config/1espt/          @benbp @weshaggard
+/sdk/template/			 @hallipr
 
 # Add owners for notifications for specific pipelines
 /eng/common/pipelines/codeowners-linter.yml       @rickwinter