fix(runner): remove redundant EnableRepoOverride from parent runner command

The -R flag was being added at the parent runner command level via cmdutils.EnableRepoOverride, causing it to appear in generated docs for all runner subcommands, including those that don't use it (delete, update). Subcommands that need -R (assign, unassign, list) already call EnableRepoOverride individually. Closes #8189 (closed) (Part 1)