Merge branch '373853-incident-tag-create-api' into 'master'

Add create mutation for creating timeline event tags on a project

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/102870



Merged-by: Michael Kozono <mkozono@gitlab.com>
Approved-by: Bishwa Hang Rai <bhrai@gitlab.com>
Approved-by: Michael Kozono <mkozono@gitlab.com>
Co-authored-by: Rajendra Kadam <rkadam@gitlab.com>