[BUGFIX] Fix birthday (validated to an int)

Classes/Domain/Model/JobApplication.php

@@ -287,17 +287,17 @@ class JobApplication extends AbstractEntity {
 	}
 
 	/**
-	 * @return int
+	 * @return string
 	 */
 	public function getBirthDate() {
 		return $this->birthDate;
 	}
 
 	/**
-	 * @param int $birthDate
+	 * @param string $birthDate
 	 */
 	public function setBirthDate($birthDate) {
-		$this->birthDate = (int) $birthDate;
+		$this->birthDate = $birthDate;
 	}
 
 	/**