[CI] Remove auto-merge label for version increment PRs (Azure#30351)

These no longer work and it's recommended that we use GitHubs's built-in
auto-merge functionality now.

Signed-off-by: Paul Van Eck <[email protected]>

Author: pvaneck

eng/pipelines/templates/stages/archetype-python-release.yml

@@ -228,7 +228,6 @@ stages:
                           PRBranchName: increment-package-version-${{ parameters.ServiceDirectory }}-$(Build.BuildId)
                           CommitMsg: "Increment package version after release of ${{ artifact.name }}"
                           PRTitle: "Increment version for ${{ parameters.ServiceDirectory }} releases"
-                          PRLabels: "auto-merge"
                           CloseAfterOpenForTesting: '${{ parameters.TestPipeline }}'
           - ${{if and(eq(variables['Build.Reason'], 'Manual'), eq(variables['System.TeamProject'], 'internal'))}}:
             - template: /eng/pipelines/templates/jobs/smoke.tests.yml