message: Fixes client no longer sets the snippetSupport capability
diff: @@ -1217,7 +1217,9 @@ class CompletionItemFeature extends TextDocumentFeature<CompletionRegistrationOp
  }
  public fillClientCapabilities(capabilites: ClientCapabilities): void {
  - ensure(ensure(capabilites, 'textDocument')!, 'completion')!.dynamicRegistration = true;
  + let completion = ensure(ensure(capabilites, 'textDocument')!, 'completion')!;
  + completion.dynamicRegistration = true;
  + completion.completionItem = { snippetSupport: true };
  }
  public initialize(documentSelector: DocumentSelector, capabilities: ServerCapabilities): void {
  