Made control-plane NodeBalancer's name dynamic

## General:

* [X] Have you removed all sensitive information, including but not limited to access keys and passwords?
* [X] Have you checked to ensure there aren't other open or closed [Pull Requests](https://github.com/linode/cluster-api-provider-linode/pulls) for the same bug/feature/question?

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## Feature Requests:
* [X] Have you explained your rationale for why this feature is needed?
* [X] Have you offered a proposed implementation/solution?

Currently, the NodeBalancer setup for the control-plane uses a static non-dynamic name which means it can conflict with existing NodeBalancers or will prevent having multiple CAPL clusters with the same name in the same Linode account. Adding a dynamic suffix to the NB label would provide parity with the rest of the resources created by CAPL

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The [Linode Community](https://www.linode.com/community/questions/) is a great place to get additional support.

Start in the repository's control-plane NodeBalancer setup and trace how its label is constructed. Change the label so it includes a dynamic suffix, then verify that separate CAPL clusters can create distinct NodeBalancers without conflicts.

Written by the indexing model from the issue text.