Gb-io

Changed
- Bump `pyo3` dependency to `v0.21`.

Fixed
- `gb_io.dump` not extracting qualifiers from Python-created records ([42](https://github.com/althonos/gb-io.py/issues/42)).
- `Qualifier.__repr__` and various `__repr__` of `Location` subclasses not using `repr`-formatting.

Fixed
- `Complement.strand` not extracting the right attribute from the inner `Location`.

Added
- Python constructors to all types.
- Properties with getter and setters for all remaining `Record` fields.
- Documentation with API reference at https://gb-io.readthedocs.io.

Changed
- Bump `pyo3` dependency to `v0.20`.
- Add wheels for Python 3.11 and 3.12.
- Reorganize code to facilitate object creation.
- Implement copy-on-access for `Record` and `Feature` attributes.
- `strand` property to some common `Location` types.
- Make `Record.sequence` a `bytearray` to allow changing the sequence content.

Added
- `source` and `organism` properties to `Record` objects.
- Support for Python 3.11.

Changed
- Bumped `pyo3` dependency to `v0.17.3`.

Removed
- Support for Python 3.6.

Added
- `gb_io.dump` method to write one or more `Record` objects to a file.

Fixed
- Compilation issues with modern `setuptools-rust` versions.
- Avoid using `readinto` method of file-like objects when compiling for PyPy because of compatibility issues with passing `memoryview` arguments.