Fixes a bug where some library linked contracts weren't getting coverage shown in coverage report
So I think what's going on is: if the base contract (say A) deploys other contracts (say B), we link A's init bytecode, causing B's init bytecode to also get linked since it's included in A's. This is all well and good when running the fuzzer, but when generating coverage reports we look at B's bytecode directly, so we need to link that directly in order to get the correct bytecode in order to grab coverage for B
We also add an extra map in the fuzzer struct to track which libraries got deployed where (because it used to be a local variable in a function, now we need to persist until report generation)