* ci: build cache
* update build job
* rename steps, cache all builds, patch timestamps for ghc 8.10.7
* refactor, save O0 caches in master and stable builds
* update build to include toolchain fingerprint
* do not save cache on exact match
* remove caching docker from prs
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Co-authored-by: Evgeny @ SimpleX Chat <259188159+evgeny-simplex@users.noreply.github.com>
