eliminate warnings in analyzer

pkgs/markdown/lib/src/inline_parser.dart

diff --git a/pkgs/markdown/lib/src/inline_parser.dart b/pkgs/markdown/lib/src/inline_parser.dart
index e852384..c127ede 100644
--- a/pkgs/markdown/lib/src/inline_parser.dart
+++ b/pkgs/markdown/lib/src/inline_parser.dart
@@ -350,7 +350,7 @@
     : super(pattern: r'!\[');
 
   Node createNode(InlineParser parser, Match match, TagState state) {
-    Node node = super.createNode(parser, match, state);
+    var node = super.createNode(parser, match, state);
     if (resolved) return node;
     if (node == null) return null;