[analysis_server] Fix link to element model page in diagnostics

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Change-Id: I4fe3366105040b64813803b0300d2837c7c1bd4f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/435200
Reviewed-by: Samuel Rawlins <[email protected]>
Reviewed-by: Brian Wilkerson <[email protected]>
Commit-Queue: Brian Wilkerson <[email protected]>

Author: DanTup

pkg/analysis_server/lib/src/status/pages/contexts_page.dart

@@ -151,7 +151,7 @@ class ContextsPage extends DiagnosticPageWithNav {
 
     void writeFile(String file) {
       var astPath = '/ast?file=${Uri.encodeQueryComponent(file)}';
-      var elementPath = '/element?file=${Uri.encodeQueryComponent(file)}';
+      var elementPath = '/element-model?file=${Uri.encodeQueryComponent(file)}';
       var contentsPath = '/contents?file=${Uri.encodeQueryComponent(file)}';
       var hasOverlay = server.resourceProvider.hasOverlay(file);