Rename or clarify Version Updater workflow

version_updater.yml does not update the BBOT version. It only bumps the pinned nuclei and trufflehog versions in their modules. Actual version calculation and git tagging happens in tests.yml. The name misleads contributors looking for the release mechanism.

Acceptance criteria:

• Workflow renamed to reflect its purpose (e.g. "Tool Version Updater") or a comment added at the top pointing to tests.yml for release tagging
• No functional changes to either workflow