contracts-bedrock: simplify CrossDomainOwnable test

Removes usage of `CommonTest` that are not required.
Also canonicalize the import paths. This should help
to speed up the tests slightly by reducing the amount
of execution required to run the tests.

packages/contracts-bedrock/test/CrossDomainOwnable.t.sol

@@ -2,17 +2,18 @@
 pragma solidity 0.8.15;
 
 // Testing utilities
-import { Vm, VmSafe } from "forge-std/Vm.sol";
+import { VmSafe } from "forge-std/Vm.sol";
+import { Test } from "forge-std/Test.sol";
 import { CommonTest, Portal_Initializer } from "test/CommonTest.t.sol";
 
 // Libraries
 import { Bytes32AddressLib } from "@rari-capital/solmate/src/utils/Bytes32AddressLib.sol";
 
 // Target contract dependencies
-import { AddressAliasHelper } from "../src/vendor/AddressAliasHelper.sol";
+import { AddressAliasHelper } from "src/vendor/AddressAliasHelper.sol";
 
 // Target contract
-import { CrossDomainOwnable } from "../src/L2/CrossDomainOwnable.sol";
+import { CrossDomainOwnable } from "src/L2/CrossDomainOwnable.sol";
 
 contract XDomainSetter is CrossDomainOwnable {
     uint256 public value;
@@ -22,7 +23,7 @@ contract XDomainSetter is CrossDomainOwnable {
     }
 }
 
-contract CrossDomainOwnable_Test is CommonTest {
+contract CrossDomainOwnable_Test is Test {
     XDomainSetter setter;
 
     function setUp() public override {