Merge branch 'dl/test-cleanup'

Test cleanup. * dl/test-cleanup: (26 commits) t7700: stop losing return codes of git commands t7700: make references to SHA-1 generic t7700: replace egrep with grep t7700: consolidate code into test_has_duplicate_object() t7700: consolidate code into test_no_missing_in_packs() t7700: s/test -f/test_path_is_file/ t7700: move keywords onto their own line t7700: remove spaces after redirect operators t7700: drop redirections to /dev/null t7501: stop losing return codes of git commands t7501: remove spaces after redirect operators t5703: stop losing return codes of git commands t5703: simplify one-time-sed generation logic t5317: use ! grep to check for no matching lines t5317: stop losing return codes of git commands t4138: stop losing return codes of git commands t4015: use test_write_lines() t4015: stop losing return codes of git commands t3600: comment on inducing SIGPIPE in `git rm` t3600: stop losing return codes of git commands ...