osquery incorrectly connected the build of the fuzzers
with the build of the tests.
This has been fixed but the flag to build the fuzzers has been
changed too, reflect that change here.
Moreover, a flag to avoid building AWS EC2 tables
and library has been added.
Disable building them on ossfuzz, so that the CI doesn't go oom.
Soon osquery will require that the version of CMake
is not equal or higher than 3.18.0.
We can ignore such requirement since we are not making packages.
See osquery/osquery#6801
Also remove unused sed replacements. Those settings are now the default
when not using the osquery toolchain.
Coverage tests are currently failing. This is most likely due to
exhausting the container disk space. This commit removes downloaded
files and build artifacts, which are not needed for coverage tests.
Stefano Bonicatti