Added some info about APP_LOGIN in README.md.

README.md

@@ -59,6 +59,7 @@ These containers are built via Github actions that [copy the dockerfile](https:/
 | `ACCESS_TOKEN` | A [github PAT](https://docs.github.com/en/github/authenticating-to-github/creating-a-personal-access-token) to use to generate `RUNNER_TOKEN` dynamically at container start. Not using this requires a valid `RUNNER_TOKEN` |
 | `APP_ID` | The github application ID. Must be paired with `APP_PRIVATE_KEY` and should not be used with `ACCESS_TOKEN` or `RUNNER_TOKEN` |
 | `APP_PRIVATE_KEY` | The github application private key. Must be paired with `APP_ID` and should not be used with `ACCESS_TOKEN` or `RUNNER_TOKEN` |
+| `APP_LOGIN` | The github application login id. Can be paired with `APP_ID` and `APP_PRIVATE_KEY` if default value extracted from `REPO_URL` or `ORG_NAME` is not correct. Note that no default is present when `RUNNER_SCOPE` is 'enterprise'. |
 | `RUNNER_SCOPE` | The scope the runner will be registered on. Valid values are `repo`, `org` and `ent`. For 'org' and 'enterprise', `ACCESS_TOKEN` is required and `REPO_URL` is unnecessary. If 'org', requires `ORG_NAME`; if 'enterprise', requires `ENTERPRISE_NAME`. Default is 'repo'. |
 | `ORG_NAME` | The organization name for the runner to register under. Requires `RUNNER_SCOPE` to be 'org'. No default value. |
 | `ENTERPRISE_NAME` | The enterprise name for the runner to register under. Requires `RUNNER_SCOPE` to be 'enterprise'. No default value. |