add sqlite not support error

aerich/ddl/sqlite/__init__.py

@@ -1,8 +1,19 @@
+from typing import Type
+
+from tortoise import Model
 from tortoise.backends.sqlite.schema_generator import SqliteSchemaGenerator
+from tortoise.fields import Field
 
 from aerich.ddl import BaseDDL
+from aerich.exceptions import NotSupportError
 
 
 class SqliteDDL(BaseDDL):
     schema_generator_cls = SqliteSchemaGenerator
     DIALECT = SqliteSchemaGenerator.DIALECT
+
+    def drop_column(self, model: "Type[Model]", column_name: str):
+        raise NotSupportError("Drop column is not support in SQLite.")
+
+    def modify_column(self, model: "Type[Model]", field_object: Field):
+        raise NotSupportError("Modify column is not support in SQLite.")

aerich/exceptions.py

@@ -1,6 +1,4 @@
-class ConfigurationError(Exception):
+class NotSupportError(Exception):
     """
-    config error
+    raise when features not support
     """
-
-    pass