Add CI jobs to set environment_state metric

What does this MR do and why?

Describe in detail what your merge request does and why.

Content

• Add CI jobs to set environment_state metric

1. CI job to set the metric to locked state when deployment starts.
2. 2 jobs (gstg-cny and gprd-cny) to set metric to ready state when QA completes.
3. Job to set metric to baking_time state when baking time starts.
4. Job to set metric to awaiting_promotion state when baking time ends.

gitlab-com/gl-infra/delivery#20062 (closed)

Testing

• Tested that the coordinator pipeline is created successfully: https://ops.gitlab.net/gitlab-org/release/tools/-/pipelines/2958494
• Tested that the TRACK_DEPLOYMENT downstream pipeline is created successfully: https://ops.gitlab.net/gitlab-org/release/tools/-/pipelines/2958538

Procedure:

1. Modify ci/coordinated-pipeline.gitlab-ci.yml#L4 to be if: "$COORDINATOR == 'true'".
2. Push your branch to ops.
3. Make your branch a protected branch.
4. Manually start a pipeline in https://ops.gitlab.net/gitlab-org/release/tools/-/pipelines from your branch and set COORDINATOR to true.

Author Check-list

• Has documentation been updated?