Merge branch 'jx/sideband-cleanup'

The side-band demultiplexer that is used to display progress output from the remote end did not clear the line properly when the end of line hits at a packet boundary, which has been corrected. Also comes with test clean-ups. * jx/sideband-cleanup: test: refactor to use "get_abbrev_oid" to get abbrev oid test: refactor to use "test_commit" to create commits test: compare raw output, not mangle tabs and spaces sideband: don't lose clear-to-eol at packet boundary