Add post and species forms

Squashed commit of the following:
Author: Hugo PRADIER <Hugo.PRADIER2@etu.uca.fr>
Author: bastien ollier <bastien.ollier@etu.uca.fr>
Author: clfreville2 <clement.freville2@etu.uca.fr>
Reviewed on #7

src/Repository/UserRepository.php

@@ -33,6 +33,16 @@ class UserRepository extends ServiceEntityRepository implements PasswordUpgrader
         $this->getEntityManager()->flush();
     }
 
+    public function findOneByEmail(string $email): ?User
+    {
+        return $this->createQueryBuilder('u')
+            ->andWhere('u.email = :email')
+            ->setParameter('email', $email)
+            ->getQuery()
+            ->getOneOrNullResult()
+        ;
+    }
+
     //    /**
     //     * @return User[] Returns an array of User objects
     //     */