1264c2a6

By: Tom Sydney Kerckhove <syd@cs-syd.eu>

Mutation redundancy: default the analysis off (opt-in)

The redundant-test analysis is informational only — there is nothing to
assert on, so it can't gate CI — and collecting it costs the within-set
fail-fast on killed mutants.  So default --redundancy / mutationCheck's
'redundancy' to off; opt in explicitly where wanted.  The in-repo example
check opts in so the feature stays exercised end-to-end in CI.