feat: add create holiday component (#1195)

Fixes: #154

src/app/organization/organization.service.ts

@@ -608,6 +608,15 @@ export class OrganizationService {
     return this.http.get('/holidays/template');
   }
 
+  /**
+   * Create Holiday.
+   * @param holidayData Holiday data to be created.
+   * @returns {Observable<any>}
+   */
+  createHoliday(holidayData: any): Observable<any> {
+    return this.http.post('/holidays', holidayData);
+  }
+
   /**
    * Update Holiday.
    * @param holidayId Holiday Id to be updated.