build: add ClusterFuzzLite setup

[DavidKorczynski]

The goal is to enable continuous fuzzing of libuv. There is not a lot of parsing or complex data handling in libuv so I think integrating with OSS-Fuzz is too much. However, ClusterFuzzLite can be used to run fuzzers for a small amount of seconds (set to 100 for now) for each PR to ensure nothing breaks. This commit adds ClusterFuzzLite setup as well as a fuzzer targeting various operations. The fuzzer can be extended, e.g. it would be nice to have more complex FS fuzzing, but I thought I would keep it as is for now and see if you're interested in having fuzzing.