Merge branch 'rename-execution_policy_pipelines-to-pipeline_execution_policies' into 'master'

Rename execution_policy_pipelines

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/158198



Merged-by: Marcos Rocha <mrocha@gitlab.com>
Approved-by: Furkan Ayhan <furkanayhn@gmail.com>
Approved-by: Marcos Rocha <mrocha@gitlab.com>
Reviewed-by: Furkan Ayhan <furkanayhn@gmail.com>
Co-authored-by: Andy Soiron <asoiron@gitlab.com>