root test file creation

libs/remix-ui/solidity-unit-testing/src/lib/solidity-unit-testing.tsx

@@ -672,6 +672,7 @@ export const SolidityUnitTesting = (props: Record<string, any>) => { // eslint-d
               value={inputPathValue}
               title="Press 'Enter' to change the path for test files."
               style={{ backgroundImage: "var(--primary)" }}
+              onKeyDown={() => { if (inputPathValue === '/') setInputPathValue('')} }
               onKeyUp={handleTestDirInput}
               onChange={handleEnter}
               onClick = {() => { if (inputPathValue === '/') setInputPathValue('')} }