tests: add missing parens in test-obsolete-bundle-strip.t The "(not ${revs})" was missing parens around ${revs}, so when revs was "A + B", it became "(not A + B)" when actually "(not (A + B))" was intended. Fixing that leads to some more testing of strip. Similarly, the parens were missing in "${revs}::", making it "A + B::" instead of "(A + B)::". Thanks to Yuya for noticing this part. This did not affect any existing tests.