Bump haml from 4.0.6 to 5.1.2

Bumps [haml](https://github.com/haml/haml) from 4.0.6 to 5.1.2.
- [Release notes](https://github.com/haml/haml/releases)
- [Changelog](https://github.com/haml/haml/blob/master/CHANGELOG.md)
- [Commits](haml/haml@4.0.6...v5.1.2)

Signed-off-by: dependabot[bot] <support@github.com>

Gemfile.lock

@@ -39,7 +39,8 @@ GEM
     erubis (2.7.0)
     execjs (2.3.0)
     ffi (1.13.1)
-    haml (4.0.6)
+    haml (5.1.2)
+      temple (>= 0.8.0)
       tilt
     hike (1.2.3)
     hitimes (1.2.2)
@@ -121,6 +122,7 @@ GEM
     sprockets-sass (1.3.1)
       sprockets (~> 2.0)
       tilt (~> 1.1)
+    temple (0.8.2)
     thor (0.19.1)
     thread_safe (0.3.4)
     tilt (1.4.1)