The following error is presented on the wildfly quickstarts 10.x branch for the wildfly-helloworld-ws project:

Multiple annotations found at this line:

• schema_reference.4: Failed to read schema document 'http://jboss.org/schema/arquillian/arquillian_1_0.xsd', because 1) could not
  find the document; 2) the document could not be read; 3) the root element of the document is not <xsd:schema>.
• cvc-elt.1: Cannot find the declaration of element 'arquillian'.

After viewing the xsd at http://jboss.org/schema/arquillian/arquillian_1_0.xsd, it's shown that the root element is `schema` rather than `xsd:schema`