* Fix command `pack` issue: if using `--src` in the option `--xoptions`, pyarmor raises excpetion `no entry script found`
* Change core version and spp library version to **r50.4**
* Support `sppmode` for Python3.7~3.10 in platforms: darwin.aarch64, linux.aarch64
* Support `sppmode` for Python 3.10 in platforms: windows.x86_64, linux.x86_64, darwin.x86_64, darwin.aarch64, linux.aarch64
* Fix `sppmode` bug: the result of inplace op for attribute is not right. For example, after `self.a += 1`, `self.a` isn't increased in old version.
* Fix `sppmode` bug: AnnAssign is ignored. For example, after `x: int = 3`, `x` still is undefined in old version.