fix(renovate): fix dry-run mode for manual trigger (#252)

Even though we have `type: boolean` on the input, in [run logs], we can
see that we get a string when using it:

```
....Evaluating String:
....=> 'inputs'
..=> Object
..Evaluating String:
..=> 'dry-run'
=> 'false'
```

So we'll need to compare with `'true`` as a string. Sad face.

[run logs]: https://github.com/grafana/shared-workflows/actions/runs/10940222859/job/30372257412

.github/workflows/renovate.yml

@@ -57,7 +57,7 @@ jobs:
  # run. By default, Renovate will clone the main/default branch.
  RENOVATE_BASE_BRANCHES: ${{ github.event_name == 'pull_request' && github.event.pull_request.head.ref || null }}
  # Dry run if the event is pull_request, or workflow_dispatch AND the dry-run input is true
- RENOVATE_DRY_RUN: ${{ github.event_name == 'pull_request' || (github.event_name == 'workflow_dispatch' && github.event.inputs.dry-run) && 'full' || null }}
+ RENOVATE_DRY_RUN: ${{ (github.event_name == 'pull_request' || (github.event_name == 'workflow_dispatch' && github.event.inputs.dry-run == 'true')) && 'full' || null }}
  RENOVATE_PLATFORM: github
  RENOVATE_REPOSITORIES: ${{ github.repository }}
  RENOVATE_USERNAME: GrafanaRenovateBot