* fix libfuzzer_libpng_cmin
* fix libfuzzer_libpng_ctx
* revert libfuzzer_libpng_cmin and check ci by grepping broker stdout result instead
* revert libfuzzer_libpng_ctx and check ci by grepping broker stdout result instead
* add check ci for fuzzers
* add check ci for fuzzers
* add check ci
* add fuzzbench test
* add validation for qemu fuzzer
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Co-authored-by: Dongjia "toka" Zhang <tokazerkje@outlook.com>
* build fuzzers with shared cargo target dir
* Make external build scripts aware of CARGO_TARGET_DIR
* fix libmozjpeg fuzzer with shared target dir
* fix cargo-make default value for CARGO_TARGET_DIR
* avoid ./ in cargo-make for windows compat
* CI: cargo-hack's --feature-powerset is too powerful
* fuzzer_concolic: support CARGO_TARGET_DIR
* ci: install z3 to avoid building from source
* ci: update actions
* ci: test nightly features with nightly rust
* test_all_fuzzers: try pruning more compilation artifacts
* ci: fix nightly feature check
* ci: apply rust-cache action after checkout (d'oh)
The rust-cache action populates the checkout directory, which is promply
deleted by the checkout action during checkout.. whoops!
