Add error handling for uninstallable packages to `opentelemetry-bootstrap -a install`

[ocelotl]

Right now we are doing this error handling here. It should be here.

The situation we are right now is that if we add a new instrumentation that does not have a third-party package as a dependency (like threading), then it won't be added to the default_instrumentations as it should. This happens because the script that gets all instrumentations won't get this instrumentation because it first checks if it is in Pypi (it is obviously not because we are just adding it to the repo).