api: add api to list and delete memory entries

[ParthS007]

Proposed changes

Ref: https://github.com/WeblateOrg/weblate/issues/6440

• Add API for listing and deleting memory entries

Checklist

• [x] Lint and unit tests pass locally with my changes.
• [x] I have added tests that prove my fix is effective or that my feature works.
• [x] I have added documentation to describe my feature.
• [x] I have squashed my commits into logic units.
• [x] I have described the changes in the commit messages.

Other information

@nijel Please let me know what else I can add in the documentation and for the API test. Thanks