test: add mustCall() to test-inspector-contexts
In test-inspector-contexts, if mainContextPromise is modified such that
the method
argument is changed to something invalid, the test still
passes and the second part of the test never runs. Use
common.mustCall()
to cause the test to fail if the second part of the
test does not run.
Refs: https://github.com/nodejs/node/issues/30519#issuecomment-558476839
Checklist
-
make -j4 test
(UNIX), orvcbuild test
(Windows) passes -
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