unittest: clean up the autocomplete_search test
unittest: clean up the autocomplete_search test

Move function specific vars to be defined in function scope instead of
class scope. Rename mymsg to err_msg.

No functional change.

Signed-off-by: Imre Deak <fbd5edba1988036c8923f0cca0cce6ac4811db29@gmail.com>

kansanmuisti/kamu,kansanmuisti/kamu,kansanmuisti/kamu,kansanmuisti/kamu,kansanmuisti/kamu