Support tags with empty or non-utf8 messages

Ref. task 6168b27c-725a-429e-b4d3-4c3c80471a5e (JamesAng/ub)

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Migrated from T64 (view on Phabricator)

added Git loader priority:High labels

Done in rDLDG61e2b1ecd061

assigned to @olasd

closed