Enable new packages list by removing feature flag

What does this MR do?

The purpose of this MR is to refactor the package list from pure haml to vue, to create the basis for new UI / UX implementation and open the way to #31817 (closed) and in the process solve: #33790 (closed).

Future work influenced by this refactor:

• #12954 (closed)
• #33948 (closed)
• #33596 (closed)
• #24078 (closed)
• #34507 (closed)

Currently the page has the following features:

• list of packages
• clicking on the package name goes to package details
• bin icon to delete the package ( if able to do so )
• sorting
• pagination

The table columns are:

• name
• version
• type
• created ( with tooltip )
• actions (delete button )

Said features are all going to be present at the end of refactor, table ui is going to be changed to gitlab-ui table component.

Screenshots

Current:

This MR is going to contain only an overview of the work and the removal of the feature flag, while the work is going to be split in other small MR.

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation created/updated or follow-up review issue created
• 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

Closes #33905 (closed) Closes #55220 (closed)