Remove config module

This module is not needed anymore.

src/msspec/calculator.py

@@ -65,7 +65,6 @@ from terminaltables.ascii_table import AsciiTable
 from msspec import iodata
 from msspec.calcio import PhagenIO
 from msspec.calcio import SpecIO
-from msspec.config import Config
 from msspec.data import electron_be
 from msspec.misc import get_call_info
 from msspec.misc import get_level_from_electron_configuration