run_tests: add newline before __main__ check
run_tests: add newline before __main__ check

Fixes new warning I saw in Debian 10:

run_tests:173:1: E305 expected 2 blank lines after class or function definition, found 1

Signed-off-by: Kalle Valo <7081a7d99b8c74c0698a728df19e3915a995d7e1@codeaurora.org>

kvalo/pwcli,kvalo/pwcli