* 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>