Build quine-mc_cluskey with opt-level=3 in dev builds

[y21]

While doing some profiling I noticed that debug clippy running on the clippy_lints crate spends 35s out of 160s in one specific code path of nonminimal_bool, which seemed a bit excessive.

I've found that just enabling optimizations for quine-mc_cluskey (used by nonminimal_bool) cuts down the part that took 35s to 3s

While this doesn't really change anything for users, this helps dogfood a bit as it cuts off about half a minute of runtime (in some of my tests, at least).

Something similar was attempted in #10576, however that involved compiling everything in release mode including clippy itself, whereas this only affects a single dependency that's compiled in parallel with something that takes longer so this should hopefully not have a negative impact in any case (and changing clippy doesn't require recompiling that dependency)

changelog: none

[rustbot]

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[flip1995]

Oh nice, good catch. This makes sense. I can't test this locally right now, so I leave the final approval to @dswij

[y21]

(I just added a comment for context since it might not be obvious why this is done)