Fix build

Author: imzyy

packages/firebase_dynamic_links/android/src/main/java/io/flutter/plugins/firebasedynamiclinks/FirebaseDynamicLinksPlugin.java

@@ -93,7 +93,7 @@ public void onMethodCall(MethodCall call, Result result) {
         buildShortDynamicLink(builder, call, createShortLinkListener(result));
         break;
       case "FirebaseDynamicLinks#getDynamicLink":
-        handleGetDynamicLink(result, Uri.parse(call.argument("url")));
+        handleGetDynamicLink(result, Uri.parse((String) call.argument("url")));
         break;
       case "FirebaseDynamicLinks#getInitialLink":
         handleGetInitialDynamicLink(result);

packages/firebase_dynamic_links/ios/Classes/FirebaseDynamicLinksPlugin.m

@@ -108,7 +108,7 @@ - (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result
           } else if (dynamicLink && dynamicLink.url) {
             result([dynamicLink.url absoluteString]);
           } else {
-            result(null);
+            result(nil);
           }
         };
     [[FIRDynamicLinks dynamicLinks] handleUniversalLink:shortLink completion:completion];