bpo-45386: Handle strftime's ValueError graciously in xmlrpc.client (GH-28765)

bpo-45386: Handle strftime's ValueError graciously in xmlrpc.client (GH-28765)

At import time, the xmlrpc.client module uses different date formats to
test strftime so it can format years with 4 digits consistently.
Depending on the underlying C library and its strftime implementation
some of these calls can result in ValueErrors, blocking the
xmlrpc.client module from being imported.

This commit changes the behavior of this bit of code to react to
ValueError exceptions, treating the format that caused them as an
non-viable option.