Add jest tests for twenty-front (#2983)

* Add jest tests for twenty-front

Co-authored-by: v1b3m <vibenjamin6@gmail.com>

* Fix tests

---------

Co-authored-by: gitstart-twenty <gitstart-twenty@users.noreply.github.com>
Co-authored-by: v1b3m <vibenjamin6@gmail.com>
Co-authored-by: Charles Bochet <charles@twenty.com>

packages/twenty-front/src/utils/__tests__/isDefined.test.ts

@@ -0,0 +1,19 @@
+import { isDefined } from '~/utils/isDefined';
+
+describe('isDefined', () => {
+  it('should return true for a NonNullable value', () => {
+    expect(isDefined(1)).toBe(true);
+  });
+
+  it('should return true for a NonNullable value', () => {
+    expect(isDefined('')).toBe(true);
+  });
+
+  it('should return false for a null value', () => {
+    expect(isDefined(null)).toBe(false);
+  });
+
+  it('should return false for an undefined value', () => {
+    expect(isDefined(undefined)).toBe(false);
+  });
+});