require app extension api only on watchOS

AFNetworking.xcodeproj/project.pbxproj

@@ -1390,6 +1390,7 @@
 		2995226B1BBF129200859F49 /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				APPLICATION_EXTENSION_API_ONLY = YES;
 				BITCODE_GENERATION_MODE = marker;
 				DEFINES_MODULE = YES;
 				DYLIB_COMPATIBILITY_VERSION = 1;
@@ -1411,6 +1412,7 @@
 		2995226C1BBF129200859F49 /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				APPLICATION_EXTENSION_API_ONLY = YES;
 				BITCODE_GENERATION_MODE = bitcode;
 				DEFINES_MODULE = YES;
 				DYLIB_COMPATIBILITY_VERSION = 1;