Bugfix: SubFile.seek for unsignedinteger

[pressler-vsc]

Description

@bombaci-vsc found some unintuitive behavior with SubFile.seek when used with numpy scalar types. An example can be seen running the new test in main:

            # seeking works with  int-like
            subfile.seek(np.uint8(24), os.SEEK_SET)
>           subfile.seek(-8, os.SEEK_CUR)

test/test_core.py:790: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

self = <jbpy.core.SubFile object at 0x7f9947be7620>, offset = -8, whence = 1

    def seek(self, offset: int, whence: int = 0) -> int:
        """
        Seek to a position within the subfile.
    
        Parameters
        ----------
        offset : int
            Offset to seek
        whence : int
            0 (start), 1 (current), or 2 (end of subfile)
    
        Returns
        -------
        int
            Current offset in the SubFile
        """
        if whence == 0:
            new_pos = offset
        elif whence == 1:
>           new_pos = self._pos + offset
                      ^^^^^^^^^^^^^^^^^^
E           OverflowError: Python integer -8 out of bounds for uint8

jbpy/core.py:87: OverflowError
==================================================================================================================================================================== short test summary info =====================================================================================================================================================================
FAILED test/test_core.py::test_subfile - OverflowError: Python integer -8 out of bounds for uint8
======================================================================================================================================================================= 1 failed in 0.73s ========================================================================================================================================================================
                                                                                                                                                                                                                                                                                                                                                                  

Wrapping a few things in int seems like a reasonable remedy.