fix(ci): clear alpine/git entrypoint in tag job

alpine/git sets ENTRYPOINT ["git"], so GitLab's shell executor was invoking
`git sh <script>` instead of `sh <script>`. Override with entrypoint: [""].

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitlab-ci.yml

@@ -17,7 +17,9 @@ test:
 
 tag:
   stage: tag
-  image: alpine/git
+  image:
+    name: alpine/git
+    entrypoint: [""]
   script:
     - git tag "v${CI_PIPELINE_IID}"
     - git push "https://gitlab-ci-token:${CI_JOB_TOKEN}@${CI_SERVER_HOST}/${CI_PROJECT_PATH}.git" "v${CI_PIPELINE_IID}"