Fix assert unreachable, remove unused variables (#13753)

Small code cleanup

packages/twenty-front/src/modules/workflow/utils/__tests__/assertUnreachable.test.ts

@@ -1,13 +0,0 @@
-import { assertUnreachable } from '@/workflow/utils/assertUnreachable';
-
-it('throws when argument is not never', () => {
-  expect(() => {
-    assertUnreachable(42 as never);
-  }).toThrow();
-});
-
-it('throws with the provided error message when argument is not never', () => {
-  expect(() => {
-    assertUnreachable(42 as never, 'Custom error!');
-  }).toThrow('Custom error!');
-});

packages/twenty-front/src/modules/workflow/utils/assertUnreachable.ts

@@ -1,3 +0,0 @@
-export const assertUnreachable = (x: never, errorMessage?: string): never => {
-  throw new Error(errorMessage ?? "Didn't expect to get here.");
-};