Noted that tox is the preferred unit tester.

This bug and fix is not about deleting run_tests.sh.
The change to delete run_tests.sh has been abandoned.
Thus the documentation of run_tests.sh remains.

Change-Id: Ia0a883260affc56c148dbebc5e3a49acb36b067e
Closes-Bug: #1282393
Merge "Noted that tox is the preferred unit tester."