List dependencies which belong to this BOM but should probably be extracted

### Issue description

The following dependencies are present in this BOM, but are used in one or more Micronaut modules. In order to avoid depending on the `platform` BOM to get a dependency version, those dependencies should instead be extracted:

- rxjava2 (defined in `micronaut-rxjava2` so probably should be removed)
- reactor
- kotlin-coroutines

