Fix FutureWarning about _indent defined with functools.partial().

FutureWarning: functools.partial will be a method descriptor in
future Python versions; wrap it in staticmethod() if you want to
preserve the old behavior

Author: maksverver

src/reader/_storage/_sql_utils.py

@@ -196,7 +196,7 @@ def _lines_keyword(self, keyword: str, things: list[_Thing]) -> Iterable[str]:
 
             yield '\n'
 
-    _indent = functools.partial(textwrap.indent, prefix='    ')
+    _indent = staticmethod(functools.partial(textwrap.indent, prefix='    '))
 
 
 if TYPE_CHECKING:  # pragma: no cover