Migrate Typescript to `~4.6.3`

[mikesposito]

In order to be able to migrate the @metamask/eth-json-rpc-provider package into the core monorepo, the typescript versions of the packages should match.

@metamask/eth-json-rpc-provider is currently using typescript with version ~4.8.4. We should use version ~4.6.3.

[legobeat]

Related:

• devDeps: @metamask/eslint-config*->12.1.0 #1523

I do think that it would be more appropriate to upgrade and consolidate on at least 4.8. I could see valid arguments for any minor version above that as well, but it seems backwards consolidating on this older version. Any reason for 4.6 that makes it desired that I'm missing?