Feat: add sad path test and exceptions for update and delete

backend/repository/tribe_sqlite_repository.py

@@ -28,6 +28,13 @@ class TribeSQLiteRepository(AbstractRepository):
         )
 
     def update(self, name: str, tribe: Tribe) -> None:
+        tribes = self.list()
+
+        if name not in map(lambda x: x.name, tribes):
+            raise TribeRepositoryError(
+                f"The tribe {name} doesn't exists. Can't update it"
+            )
+
         self.conn.execute(
             """
             UPDATE tribes SET name=:newname, level=:newlevel WHERE name=:name
@@ -66,6 +73,12 @@ class TribeSQLiteRepository(AbstractRepository):
         return [Tribe(*r) for r in rows]
 
     def delete(self, tribe: Tribe) -> None:
+        tribes = self.list()
+        if tribe.name not in map(lambda x: x.name, tribes):
+            raise TribeRepositoryError(
+                f"The tribe {tribe.name} doesn't exists. Can't delete it."
+            )
+
         self.conn.execute(
             """
             DELETE FROM tribes WHERE name=:name