### Description of the change
This addresses 2 bugs regarding configured runner labels:
- `Cannot find: node in PATH` due to a default label that matches the runner host, not the docker-in-docker environment
- After changing the runner config, users have to manually replace the StatefulSet Pod of the runner
### Benefits
- Out-of-the-box functioning node environment
- Auto-updated runner config on changes in values
### Applicable issues
- fixes https://gitea.com/gitea/helm-chart/issues/728
- fixes https://gitea.com/gitea/helm-chart/issues/725
### Additional information
With removing the default labels from `values.yaml`, the act runner defaults will be used for new runners which fixes the "missing node" issue.
I had issues replacing the labels once the Chart defaults were used, so users might have to replace their runner manually if this is an issue.
### Checklist
- [x] Templating unittests are added
Signed-off-by: justusbunsi <sk.bunsenbrenner@gmail.com>
Reviewed-on: https://gitea.com/gitea/helm-chart/pulls/739
Co-authored-by: justusbunsi <sk.bunsenbrenner@gmail.com>
Co-committed-by: justusbunsi <sk.bunsenbrenner@gmail.com>
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