test: rename test contract to "FooTest"

test/Foo.t.sol

@@ -7,7 +7,7 @@ import { StdCheats } from "forge-std/StdCheats.sol";
 
 /// @dev See the "Writing Tests" section in the Foundry Book if this is your first time with Forge.
 /// https://book.getfoundry.sh/forge/writing-tests
-contract ContractTest is PRBTest, StdCheats {
+contract FooTest is PRBTest, StdCheats {
     function setUp() public {
         // solhint-disable-previous-line no-empty-blocks
     }