test: avoid using debugdrawdag in 'test-topic-debugcb.t'
The 'debugdrawdag' utility adds local tags that prevent hidden changeset to get
hidden. We will do without that extension for now.
#require test-repo$checkflake8(){>if!(whichflake8>/dev/null);then>echoskipped:missingtool:flake8;>exit80;>fi;>};$checkflake8CopiedfromMercurialcore(60ee2593a270)$cd"`dirname "$TESTDIR"`"runflake8ifitexists;ifitdoesn't, then just skip $ hg files -0 'set:(**.pyorgrep("^#!.*python"))-removed()' 2>/dev/null \ > | xargs -0 flake8