eth-json-rpc-provider: Replace use of any with proper types (non-test files only)

[mcmire]

Look for the following string in non-test files to find these: // TODO: Replace `any` with type

At time of writing, there were 2 instances.

• Blocked by Make SafeEventEmitterProvider type-compatible with Ethereum request libraries #4095

[MajorLift]

The any usage here occurs in the send and sendAsync methods of the SafeEventEmitterProvider class. Both methods are slated to be deprecated but not removed by this proposal (Align provider with Ethereum request libraries).

Therefore, we could replace the TODO annotations with something like the following and close this ticket:
// The any usage in this legacy type is being preserved for backward compatibility.

[MajorLift]

This can probably wait until the provider alignment proposal moves forward, and we can be certain that send/sendAsync will be sunsetted as legacy methods.