Upgrade to release 1.6.3:
- add missing .h files to sdist tarball
- use `Py_SET_TYPE()` and `Py_SET_SIZE()` for Python 3.10
- add official Python 3.10 support
- fix slice assignement to same object, e.g. a[2::] = a or
a[::-1] = a
- add bitarray.h
Signed-off-by: Leon Anavi <leon.anavi@konsulko.com>
Acked-by: Trevor Gamblin <trevor.gamblin@windriver.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>