Since the `exec` command does not use labels from `.runner`, there is no existing way to specify which Docker image to use for task execution.
This adds an `--image` flag for specifying it manually. The default remains `node:16-bullseye`.
Co-authored-by: Lunny Xiao <[email protected]>
Reviewed-on: https://gitea.com/gitea/act_runner/pulls/83
Reviewed-by: Jason Song <[email protected]>
Reviewed-by: Lunny Xiao <[email protected]>
Co-authored-by: telackey <[email protected]>
Co-committed-by: telackey <[email protected]>
