Prior to this commit, the redirectedUrl() and forwardedUrl() methods in
MockMvcResultMatchers supported fully constructed URLs and URLs
containing Ant-style path patterns. However, URI templates were not
supported for these result matchers even though the request path can be
built using URL templates -- for example, via the get() and post()
methods in MockMvcRequestBuilders.
This commit addresses this shortcoming by allowing users to supply a
URL template instead of a fully constructed URL to redirectedUrl() and
forwardedUrl(). To populate the URL template, template variables may be
supplied to redirectedUrl() and forwardedUrl() as var-args.
Issue: SPR-14790