Update standards version to 4.5.1, no changes needed.

Changes-By: lintian-brush
Fixes: lintian: out-of-date-standards-version
See-also: https://lintian.debian.org/tags/out-of-date-standards-version.html

debian/control

@@ -10,7 +10,7 @@ Build-Depends: debhelper-compat (= 13),
                rake,
                ruby-rspec,
                ruby-webmock
-Standards-Version: 4.5.0
+Standards-Version: 4.5.1
 Vcs-Browser: https://salsa.debian.org/ruby-team/gist
 Vcs-Git: https://salsa.debian.org/ruby-team/gist.git
 Homepage: https://github.com/defunkt/gist