maint(ct): clean up OVM_ETH tests (#2493)

Cleans up OVM_ETH tests using the same techniques as other cleanup PRs.
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

packages/contracts/test/contracts/L2/predeploys/OVM_ETH.spec.ts

 /* External Imports */
 import { ethers } from 'hardhat'
-import { ContractFactory, Contract, Signer } from 'ethers'
+import { Contract } from 'ethers'
+import { SignerWithAddress } from '@nomiclabs/hardhat-ethers/signers'
 
 import { expect } from '../../../setup'
+import { deploy } from '../../../helpers'
 
 describe('OVM_ETH', () => {
-  let signer1: Signer
-  let signer2: Signer
+  let signer1: SignerWithAddress
+  let signer2: SignerWithAddress
   before(async () => {
     ;[signer1, signer2] = await ethers.getSigners()
   })
 
-  let Factory__OVM_ETH: ContractFactory
-  before(async () => {
-    Factory__OVM_ETH = await ethers.getContractFactory('OVM_ETH')
-  })
-
   let OVM_ETH: Contract
   beforeEach(async () => {
-    OVM_ETH = await Factory__OVM_ETH.deploy()
+    OVM_ETH = await deploy('OVM_ETH')
   })
 
   describe('transfer', () => {
     it('should revert', async () => {
-      await expect(
-        OVM_ETH.transfer(await signer2.getAddress(), 100)
-      ).to.be.revertedWith(
+      await expect(OVM_ETH.transfer(signer2.address, 100)).to.be.revertedWith(
         'OVM_ETH: transfer is disabled pending further community discussion.'
       )
     })
@@ -33,9 +28,7 @@ describe('OVM_ETH', () => {
 
   describe('approve', () => {
     it('should revert', async () => {
-      await expect(
-        OVM_ETH.approve(await signer2.getAddress(), 100)
-      ).to.be.revertedWith(
+      await expect(OVM_ETH.approve(signer2.address, 100)).to.be.revertedWith(
         'OVM_ETH: approve is disabled pending further community discussion.'
       )
     })
@@ -44,11 +37,7 @@ describe('OVM_ETH', () => {
   describe('transferFrom', () => {
     it('should revert', async () => {
       await expect(
-        OVM_ETH.transferFrom(
-          await signer1.getAddress(),
-          await signer2.getAddress(),
-          100
-        )
+        OVM_ETH.transferFrom(signer1.address, signer2.address, 100)
       ).to.be.revertedWith(
         'OVM_ETH: transferFrom is disabled pending further community discussion.'
       )
@@ -58,7 +47,7 @@ describe('OVM_ETH', () => {
   describe('increaseAllowance', () => {
     it('should revert', async () => {
       await expect(
-        OVM_ETH.increaseAllowance(await signer2.getAddress(), 100)
+        OVM_ETH.increaseAllowance(signer2.address, 100)
       ).to.be.revertedWith(
         'OVM_ETH: increaseAllowance is disabled pending further community discussion.'
       )
@@ -68,7 +57,7 @@ describe('OVM_ETH', () => {
   describe('decreaseAllowance', () => {
     it('should revert', async () => {
       await expect(
-        OVM_ETH.decreaseAllowance(await signer2.getAddress(), 100)
+        OVM_ETH.decreaseAllowance(signer2.address, 100)
       ).to.be.revertedWith(
         'OVM_ETH: decreaseAllowance is disabled pending further community discussion.'
       )