`build-scan-publish` is ignored when `onlyIf { false }` was used

As documented on https://docs.gradle.com/develocity/gradle-plugin/current/ at `Publishing on demand` I configured `onlyIf { false }` to only publish build scans on demand and be able to use `buildScanPublishPrevious`.

In this action I set `build-scan-publish: 'true'` to always publish build scan when run on GHA.

But no build scan is published on execution.

I don't want to use `--scan` right now as the build is still on `8.0.2` and I don't have the time to upgrade right now, and using it with `8.0.2` would fail the build as latest Develocity plugin is applied which would then complain about Enterprise plugin added by `--scan`.

The work-around I am using now is `onlyIf { System.getenv("DEVELOCITY_INJECTION_ENABLED").toBoolean() }`, but it would be nice if it either just worked or at the very least be included in the documentation of this action.

Start by tracing how the `build-scan-publish` input is handled in the action and compare that behavior with the documented “Publishing on demand” configuration. Done means the input works when `onlyIf { false }` is configured, or the action documentation clearly explains the limitation and supported workaround.

Written by the indexing model from the issue text.