Remove importUri from test.

The corresponding getter was removed from analyzer_plugin in
https://github.com/dart-lang/sdk/commit/5e2529c82e11150dbc2448f0f43aa4fcea16177b
diff --git a/angular_analyzer_plugin/test/completion_contributor_test_util.dart b/angular_analyzer_plugin/test/completion_contributor_test_util.dart
index 6b79273..e62aa51 100644
--- a/angular_analyzer_plugin/test/completion_contributor_test_util.dart
+++ b/angular_analyzer_plugin/test/completion_contributor_test_util.dart
@@ -167,7 +167,6 @@
     } else {
       expect(cs.relevance, equals(relevance), reason: completion);
     }
-    expect(cs.importUri, importUri);
     expect(cs.selectionOffset, equals(completion.length));
     expect(cs.selectionLength, equals(0));
     expect(cs.isDeprecated, equals(isDeprecated));