Update v8 used during fuzzing (#3493)

This commit updates the crate name from `rusty_v8` to `v8` as well since
the upstream bindings have sinced moved. I originally wanted to do this
to see if a fix for one of our fuzz bugs was pulled in but I don't think
the fix has been pulled in yet. Despite that it seems reasonable to go
ahead and update.

crates/fuzzing/src/oracles.rs

@@ -22,7 +22,7 @@ use wasmtime::*;
 use wasmtime_wast::WastContext;
 
 #[cfg(not(any(windows, target_arch = "s390x")))]
-pub use v8::*;
+pub use self::v8::*;
 #[cfg(not(any(windows, target_arch = "s390x")))]
 mod v8;