OAuth2 responses due to an Exception do not contain the "Pragma: no-cache" header as per specification

The "Pragma: no-cache" header and value is not returned when an exception is thrown within the context of a TokenEndpoint instance. I suggest the DefaultWebResponseExceptionTranslator#handleOAuth2Exception should be modified to set this value.

I have worked around this by creating a bean that gets loaded after the "oauth2TokenEndpoint" bean, has a property that references the "oauth2TokenEndpoint" bean, and also has an "afterPropertiesSet" method implementation that sets the "oauth2TokenEndpoint" bean with a custom class that extends DefaultWebResponseExceptionTranslator. The custom class overrides the "translate" method to add this header and value into the super's returned result.