fix(docs): remove link to removed Coreset class

Merge pull request #968 from gchq/hotfix/release_errors

Update release procedure to perform release testing before merging into main

chore: tidy changelog for 0.3.1

refs: #844

chore: Changed the format of inserting links in CHANGELOG.md.

feat: set default version in bug report template to 0.2.1

refs: #681

Merge pull request #660 from gchq/docs/update-changelog

changelog for release

Merge pull request #443 from gchq/feature/pyproject_urls

docs: add documentation, issues and changelog URLs to pyproject.toml