updated pkpy to v2.0.4

[PrimedErwin]

The previous pr is #2714 (1 month ago)

What's changed from v2.0.1 to v2.0.4

v2.0.2

1. Fix a bug of random module which uses a wrong initial seed.
2. Fix #315 about py_switchvm.
3. Improve PK_ENABLE_OS and add PK_BUILD_WITH_IPO to cmake options.
4. Add conio module which provides _kbhit and _getch functions for desktop platforms.
5. Fix True not False bug of parser.
6. Fix ** associativity bug. 2**2**3 now evaluates to 256 instead of 64.
7. Add __float__ and __int__ and __round__.
8. Add py_bindstaticmethod.
9. Fix str.split. It behaves the same as cpython now.
10. Fix a bug of closure for generator functions.
11. Support vec* unpack, e.g. x, y = vec2i(1, 2).

v2.0.3

1. fix some type annotation usage e.g. int | None.
2. fix some builtins hash functions
3. fix a severe bug of dict
4. clean up #defines
5. improve array2d
6. fix a bug of super
7. fix a bug of context manager

v2.0.4

1. add pickle module
2. raise error on mismatched eq/ne
3. fix a bug of 32-bit
4. support empty tuple ()
5. improve json

Full Changelog: pocketpy/pocketpy@v2.0.1...v2.0.4