Changes

pySim.runtime: Fix file selection by upper case hex FID

When trying to remove a file (e.g. DF.5G_ProSe, 5FF0),
there seems to be a case sensitive check when checking for the dict:
pySim/runtime.py: get_file_for_filename():

478          def get_file_for_filename(self, name: str):
479              """Get the related CardFile object for a specified filename."""
480              sels = self.selected_file.get_selectables()
481              return sels[name]

The dict sels contains 5ff0, but not 5FF0.
The type of argument name is str. So a case sensitive check will be used.

Change-Id: Idd0db1f4bbd3ee9eec20f5fd0f4371c2882950cd
Closes: OS#6898