Merge branch 'jk/test-with-x' into maint

Running tests with the "-x" option to make them verbose had some
unpleasant interactions with other features of the test suite.

* jk/test-with-x:
test-lib: disable trace when test is not verbose
test-lib: turn off "-x" tracing during chain-lint check

diff --cc t/test-lib.sh
Simple merge