Merge branch 'ib/t3700-add-chmod-x-updates' into tg/add-chmod+x-fix

Newly added tests to this topic uses helper functions that did not exist back when the bug being fixed by the topic was introduced. * ib/t3700-add-chmod-x-updates: t3700: add a test_mode_in_index helper function t3700: merge two tests into one t3700: remove unwanted leftover files before running new tests