fix: generated workflows include wrong path for reusable workflow

[Renan]

Description

When generating a publishable plugin, the generated workflows for the platform implementations are wrong.

Steps To Reproduce

1. Generate a publishable plugin
2. Open a generated workflow under .github/workflows/generated_plugin_<platform>.yaml
3. Panaworkflow will look like:

pana:
    uses: VeryGoodOpenSource/very_good_workflows/brick/__brick__/generated_plugin/.github/workflows/pana.yml@v1

Expected Behavior

When it should be:

pana:
    uses: VeryGoodOpenSource/very_good_workflows/.github/workflows/pana.yml@v1

[Renan]

The proposed solution breaks the generator

[Renan]

Fix landed on #107