Update worker feature categories to match product changes

What does this MR do?

In the two months since the last update, there have been a few product reorganisations of the GitLab feature categories. This change updates the feature categories list from stages.yml and updates several workers to match the new feature categories.

cc EMs:

• @lmcandrew / @jeremy for gitlab-com/www-gitlab-com!36874 (merged) groups renamed to subgroups
• @sengelhard / @danielgruesso for gitlab-com/www-gitlab-com!34597 (merged) kubernetes_configuration renamed to kubernetes_management
• @johnhope gitlab-com/www-gitlab-com!29027 (merged) agile_project_management renamed to epics

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team