[path] fix tests to compile/run with wasm

Author: kevmoo

pkgs/path/pubspec.yaml

@@ -13,3 +13,4 @@ environment:
 dev_dependencies:
   dart_flutter_team_lints: ^3.0.0
   test: ^1.16.6
+  web: ^1.0.0

pkgs/path/test/browser_test.dart

@@ -5,10 +5,9 @@
 @TestOn('browser')
 library;
 
-import 'dart:html';
-
 import 'package:path/path.dart' as path;
 import 'package:test/test.dart';
+import 'package:web/web.dart';
 
 void main() {
   group('new Context()', () {