login_auth_test.py should not be run in full suite

[d-w-moore]

login_auth_test.py [...] requires specific setups, so shouldn't be run as a matter of course in the PRC suite. That will be fixed in v2.1.0 (see issue #502. we'll be renaming it to run in a BATS test and that should defeat the pattern matching that causes it to be picked up in the routine run of the full suite).

Originally posted by @d-w-moore in #531 (comment)

[alanking]

This file has been renamed to login_auth_test_must_run_manually.py to prevent it from running with the full suite. #502 will include the effort to turn this into a BATS test, and the BATS tests will be made to run alongside the regular suite of tests in order to prevent regressions.