Make build-fuzz work again, test it on CI

[kostko]

Fixes #2695

[codecov]

Codecov Report

Merging #2696 into master will decrease coverage by 0.08%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #2696      +/-   ##
==========================================
- Coverage    63.2%   63.11%   -0.09%     
==========================================
  Files         376      376              
  Lines       35324    35325       +1     
==========================================
- Hits        22327    22297      -30     
- Misses      10202    10227      +25     
- Partials     2795     2801       +6

Impacted Files	Coverage Δ
...ensus/tendermint/apps/staking/proposing_rewards.go	77.77% <100%> (+0.85%)	⬆️
go/consensus/tendermint/api/api.go	73.58% <0%> (-15.1%)	⬇️
go/worker/compute/executor/committee/state.go	74.07% <0%> (-11.12%)	⬇️
go/storage/api/root_cache.go	72.41% <0%> (-6.9%)	⬇️
go/common/cbor/codec.go	64.7% <0%> (-5.89%)	⬇️
go/worker/common/host/protocol/protocol.go	65.67% <0%> (-5.23%)	⬇️
go/worker/compute/executor/committee/node.go	62% <0%> (-4.14%)	⬇️
go/storage/mkvs/urkel/urkel.go	84.61% <0%> (-3.85%)	⬇️
go/storage/mkvs/urkel/insert.go	87.5% <0%> (-2.78%)	⬇️
go/storage/metrics.go	77.77% <0%> (-2.57%)	⬇️
... and 18 more

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