HighContrast: Add sass parsing script

Just a copy of what we have next door in Adwaita.

diff --git a/gtk/resources/theme/HighContrast/parse-sass.sh b/gtk/resources/theme/HighContrast/parse-sass.sh
new file mode 100755 (executable)
index 0000000..e9cda25
--- /dev/null
+++ b/gtk/resources/theme/HighContrast/parse-sass.sh
@@ -0,0 +1,3 @@
+#!/usr/bin/bash
+
+bundle exec sass --update --sourcemap=none .