Remove project access tokens from the personal access tokens list in Credentials Inventory

Overview

Currently, project access tokens appear in the "Personal Access Tokens" list in the credentials inventory. Once !79645 (merged) is merged, those tokens will appear in both lists. This is both redundant and potentially confusing.

Proposal

• Remove all project access tokens from the credentials inventory in the "Personal Access Tokens" tab.
• Create migration to remove all project bot users that do not have a personal access token. (This is risky and we need to decide if the potential impact is worth the risk.)

Potential Impact

Project access tokens revoked from the personal access token's tab could create a situation where bot users remain in existance without an associated access token.

Related to #243833 (closed).