Ensure HTTP method case uniformity

Box's validate_v1_path http method name should be lowercase.

Author: NyanHelsing

waterbutler/providers/box/provider.py

@@ -53,7 +53,7 @@ async def validate_v1_path(self, path: str, **kwargs) -> WaterButlerPath:
             raise exceptions.NotFoundError(str(path))
 
         response = await self.make_request(
-            'get',
+            'GET',
             self.build_url(files_or_folders, obj_id, fields='id,name,path_collection'),
             expects=(200, 404,),
             throws=exceptions.MetadataError,