Fix form clearing for company size

ee/app/assets/javascripts/hand_raise_leads/hand_raise_lead/components/hand_raise_lead_button.vue

@@ -151,7 +151,7 @@ export default {
       this.firstName = '';
       this.lastName = '';
       this.companyName = '';
-      this.companySize = '';
+      this.companySize = null;
       this.phoneNumber = '';
       this.country = null;
       this.state = null;

ee/spec/frontend/hand_raise_leads/components/hand_raise_lead_button_spec.js

@@ -150,6 +150,11 @@ describe('HandRaiseLeadButton', () => {
         comment: 'comment',
         ...formData,
       });
+
+      ['firstName', 'lastName', 'companyName', 'phoneNumber'].forEach((f) =>
+        expect(wrapper.vm[f]).toBe(''),
+      );
+      ['companySize', 'country', 'state'].forEach((f) => expect(wrapper.vm[f]).toBe(null));
     });
   });
 });