Improve performance of constructing query strings with int values (#1259)

Author: bdraco

CHANGES/1259.misc.rst

@@ -0,0 +1 @@
+Improved performance of constructing query strings with ``int`` values -- by :user:`bdraco`.

yarl/_url.py

@@ -1280,6 +1280,8 @@ def _query_var(v: QueryVariable) -> str:
             if TYPE_CHECKING:
                 assert isinstance(v, str)
             return v
+        if cls is int:  # Fast path for non-subclassed int
+            return str(v)
         if issubclass(cls, float):
             if TYPE_CHECKING:
                 assert isinstance(v, float)