[ios] Implement vectorEffect nonScalingStroke / non-scaling-stroke

Add missing header file

ios/Utils/RNSVGVectorEffect.h

@@ -0,0 +1,14 @@
+/**
+ * Copyright (c) 2015-present, react-native-community.
+ * All rights reserved.
+ *
+ * This source code is licensed under the MIT-style license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+typedef CF_ENUM(int32_t, RNSVGVectorEffect) {
+    kRNSVGVectorEffectDefault,
+    kRNSVGVectorEffectNonScalingStroke,
+    kRNSVGVectorEffectInherit,
+    kRNSVGVectorEffectUri
+};