Bump middleman-syntax from 3.0.0 to 3.2.0 (olivierlacan#308)

Bumps [middleman-syntax](https://github.com/middleman/middleman-syntax) from 3.0.0 to 3.2.0.
- [Release notes](https://github.com/middleman/middleman-syntax/releases)
- [Changelog](https://github.com/middleman/middleman-syntax/blob/master/CHANGELOG.md)
- [Commits](https://github.com/middleman/middleman-syntax/commits)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Gemfile.lock

@@ -10,15 +10,15 @@ GEM
       public_suffix (>= 2.0.2, < 4.0)
     autoprefixer-rails (9.4.10.2)
       execjs
-    backports (3.14.0)
+    backports (3.15.0)
     coderay (1.1.2)
     coffee-script (2.4.1)
       coffee-script-source
       execjs
     coffee-script-source (1.12.2)
     concurrent-ruby (1.1.5)
     contracts (0.13.0)
-    dotenv (2.7.2)
+    dotenv (2.7.4)
     em-websocket (0.5.1)
       eventmachine (>= 0.12.9)
       http_parser.rb (~> 0.6.0)
@@ -27,7 +27,7 @@ GEM
     execjs (2.7.0)
     fast_blank (1.0.0)
     fastimage (2.1.5)
-    ffi (1.10.0)
+    ffi (1.11.1)
     haml (5.0.4)
       temple (>= 0.8.0)
       tilt
@@ -91,9 +91,9 @@ GEM
     middleman-minify-html (3.4.1)
       htmlcompressor (~> 0.2.0)
       middleman-core (>= 3.2)
-    middleman-syntax (3.0.0)
+    middleman-syntax (3.2.0)
       middleman-core (>= 3.2)
-      rouge (~> 2.0)
+      rouge (~> 3.2)
     minitest (5.11.3)
     padrino-helpers (0.13.3.4)
       i18n (~> 0.6, >= 0.6.7)
@@ -105,16 +105,16 @@ GEM
     pry (0.12.2)
       coderay (~> 1.1.0)
       method_source (~> 0.9.0)
-    public_suffix (3.0.3)
+    public_suffix (3.1.1)
     rack (2.0.7)
     rack-livereload (0.3.16)
       rack
-    rake (12.3.2)
+    rake (12.3.3)
     rb-fsevent (0.10.3)
     rb-inotify (0.10.0)
       ffi (~> 1.0)
     redcarpet (3.5.0)
-    rouge (2.0.5)
+    rouge (3.7.0)
     sassc (2.0.1)
       ffi (~> 1.9)
       rake