Bump version and update changelog for release v4.5.0

PR Checklist

[x] Wrote a good commit message & description [see guide below].
[ ] Commit message starts with [Resolve #issue-number].
[ ] Added/Updated unit tests.
[ ] Added/Updated integration tests (if applicable).
[x] All unit tests (poetry run tox) are passing.
[ ] Used the same coding conventions as the rest of the project.
[ ] The new code passes pre-commit validations (poetry run pre-commit run --all-files).
[x] The PR relates to only one subject with a clear title. and description in grammatically correct, complete sentences.