Add some type annotations to potentially ambiguous cases.

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Status Job ID Name Coverage
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passed #6111
fp-timing
build-coq.8.6.1

00:03:00

passed #6110
fp-timing
build-coq.8.7.0

00:02:47

 
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passed #6112
opam

00:00:13

passed #6113
reverse-deps

00:00:13

 
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passed #6114
fp-timing
build-coq.8.7.dev

00:03:42