Add endpoints for "Repository" resource for job tokens

Background

With the recent rollout of granular permissions for job tokens, the next phase is to expand endpoint support for job tokens, so users do not have to rely on long-lived tokens.

Proposal

The scope of this issue is to:

• Create a new resource "Repository" for job tokens
• Add the following endpoints with read and write permissions.
• Add the read/write dropdown for the FE.

Resource	Action	Endpoint	Description
Repository	Read	GET /api/:version/projects/:id/repository/commits/:sha	Get a specific commit identified by the commit hash or name of a branch or tag.
Repository	Read	GET /api/:version/projects/:id/repository/files/:file_path/raw	Get raw file from repository
Repository	Read	GET /api/:version/projects/:id/repository/branches	Get a list of repository branches from a project.
Repository	Read	GET /projects/:id/repository/commits/:sha/merge_requests	Get a merge request that originally introduced a specific commit.
Repository	Read	GET /api/:version/projects/:id/repository/tags	Get a list of repository tags from a project.