Feat: add update_student to service

backend/service/services.py

@@ -74,3 +74,32 @@ def add_student(
 
     conn.commit()
     return student
+
+
+def update_student(
+    id: str,
+    name: str,
+    tribe: str,
+    student_repo: AbstractRepository,
+    tribe_repo: AbstractRepository,
+    conn,
+) -> Student:
+
+    try:
+        _tribe = tribe_repo.get(tribe)
+    except TribeRepositoryError:
+        raise TribeDoesNotExist(
+            f"The tribe {tribe} does not exists. Can't update a student with it"
+        )
+
+    student = Student(id=id, name=name, tribe=_tribe)
+
+    try:
+        student_repo.update(student)
+    except StudentRepositoryError:
+        raise StudentDoesExist(
+            f"The student {student.name} ({student.id=}) does not exists. Can't update it."
+        )
+
+    conn.commit()
+    return student