Twined

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Operations
- [x] Use new PR description workflow
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Contents

Operations
- [x] Use `conventional-commits` repo for CI checks

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Operations
- [x] Use LAST_RELEASE mode when compiling release notes

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Operations
- [x] Add missing `mkver.conf`

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Operations
- [x] Run `release` workflow on merge of any branch into `main`
- [x] Add [Conventional Commits](https://www.conventionalcommits.org/en/v1.0.0/) `pre-commit` hook
- [x] Replace `check-version-consistency` job with `check-semantic-version` job, which checks that the version in `setup.py` is the same as the semantic version expected by `git-mkver` given the Conventional Commits since the last tag
- [x] Add the `update-pull-request` workflow that auto-generates part of the PR description on each commit
- [x] Run `publish` test job on all branches and make it dependent on `check-semantic-version` job passing
- [x] Rename `tests` job to `run-tests`

Contents

New Features
- [x] Add file tags template to twine schema
- [x] Add file tags template validation for datasets

Breaking changes
- [x] Require datasets to be inside "datasets" field in "manifest" fields of `twine.json`
- [x] Make tags an object and add labels field to manifest schema
- [x] Separate old tags in examples and tests into labels and new tags

Minor improvements
- [x] Update tags format in examples in docs
- [x] Remove `filters` field from manifest in `twine` schema
- [x] Remove `kind` field from `manifest` schema (i.e. "multi-dataset")
- [x] Factor out manifest schema into definition in `twine` schema and use for all three manifest types
- [x] Split getting schema from validating against schema in `Twine`

Fixes
- [x] Add missing `configuration_manifest` to twine schema
- [x] Fix name of `configuration_values_schema` in `twine` schema and `twine.json` files

Testing
- [x] Use correct method in manifest validation test
- [x] Update tags format