## Why this should be merged
Importing some `avalanchego` test fixtures automatically imports
`coreth` packages that register extras, which affects testing of other
VMs that depend on `libevm`. All other registered extras can be cleared
with the pattern in this PR.
## How this works
Uses the `register.AtMostOnce` type already used in `params` and
`types`. I forgot to update the `vm` package when implementing the type.
## How this was tested
Existing unit tests.
* feat: override `vm.NewEVM()` args
* test: `vm.Hooks.OverrideNewEVMArgs`
* refactor: use `NewEVMArgs struct` in hook
* chore: `gci`
* fix: clear `vm.Hooks` at end of test
