Removed duplicated L2 election test code (#11259)

* removed L2 duplicated test code

* -- compiltation warning

* Removed duplicated L2 election test code
### Description

Using test contract inheritance to minimize duplicated code during L2 testing

### Other changes

removed unused var

### Tested

unit tested

### Related issues

- Fixes #[issue number here]

### Backwards compatibility

_Brief explanation of why these changes are/are not backwards compatible._

### Documentation

_The set of community facing docs that have been added/modified because of this change_

* Revert "Removed duplicated L2 election test code"

This reverts commit b0058c5.

* -- duplicate test

* Remove unnecessary comment

* Add whitespace

---------

Co-authored-by: Marcin Chrzanowski <[email protected]>

packages/protocol/test-sol/devchain/migration/Migration.t.sol

@@ -244,7 +244,6 @@ contract EpochManagerIntegrationTest is IntegrationTest, MigrationsConstants {
     blockTravel(vm, 43200);
     timeTravel(vm, DAY);
 
-    IERC20 _celoToken = IERC20(address(celoToken));
     vm.prank(randomAddress);
 
     (bool success, ) = address(unreleasedTreasury).call{ value: 50000 ether }("");