ci: remove github sync job

Github sync is done using repository mirroring rules instead.

.gitlab-ci.yml

@@ -12,8 +12,6 @@ variables:
   ARTIFACT_DOWNLOAD_ATTEMPTS: "10"
   GIT_SUBMODULE_STRATEGY: none
 
-  ESP_IDF_GIT: "https://gitlab-ci-token:${CI_JOB_TOKEN}@${GITLAB_HTTPS_SERVER}/espressif/esp-idf.git"
-
 .setup_idf_tools: &setup_idf_tools |
   tools/idf_tools.py --non-interactive install && eval "$(tools/idf_tools.py --non-interactive export)" || exit 1
 
@@ -148,20 +146,6 @@ deploy_docs_production:
     DOCS_DEPLOY_PATH: "$DOCS_PROD_PATH"
     DOCS_DEPLOY_URL_BASE: "https://docs.espressif.com/projects/esp-modbus"
 
-push_master_to_github:
-  stage: deploy
-  tags:
-    - deploy
-  only:
-    - master
-    - /^release\/v/
-    - /^v\d+\.\d+(\.\d+)?($|-)/
-  when: on_success
-  script:
-    - git clone --depth 1 ${ESP_IDF_GIT} esp-idf
-    - *add_gh_key_remote
-    - esp-idf/tools/ci/push_to_github.sh
-
 upload_to_component_manager:
   stage: deploy
   image: python:3.10-alpine