Make test pods optional and allow image override (#360)

### Description of the change

Make the test-connection Pod optional and override the wget container's image.

### Benefits

Allows users to enable/disabled the test-connection Pod and override the wget container's image.

### Checklist

- [X] Parameters are documented in the `values.yaml` and added to the `README.md` using [readme-generator-for-helm](https://github.com/bitnami-labs/readme-generator-for-helm)
- [X] Breaking changes are documented in the `README.md`

Co-authored-by: Umer Anwar <umer.anwar@nuance.com>
Co-authored-by: ooms97 <anwarumer97@gmail.com>
Reviewed-on: https://gitea.com/gitea/helm-chart/pulls/360
Reviewed-by: pat-s <pat-s@noreply.gitea.io>
Reviewed-by: justusbunsi <justusbunsi@noreply.gitea.io>
Co-authored-by: ooms97 <ooms97@noreply.gitea.io>
Co-committed-by: ooms97 <ooms97@noreply.gitea.io>

README.md

@@ -815,9 +815,12 @@ gitea:
 
 ### Advanced
 
-| Name               | Description                                          | Value  |
-| ------------------ | ---------------------------------------------------- | ------ |
-| `checkDeprecation` | Set it to false to skip this basic validation check. | `true` |
+| Name               | Description                                                        | Value     |
+| ------------------ | ------------------------------------------------------------------ | --------- |
+| `checkDeprecation` | Set it to false to skip this basic validation check.               | `true`    |
+| `test.enabled`     | Set it to false to disable test-connection Pod.                    | `true`    |
+| `test.image.name`  | Image name for the wget container used in the test-connection Pod. | `busybox` |
+| `test.image.tag`   | Image tag for the wget container used in the test-connection Pod.  | `latest`  |
 
 ## Contributing