Fix remove unused

Gemfile.lock

@@ -1,12 +1,3 @@
-GIT
-  remote: https://github.com/awood/rack-jekyll
-  revision: 86f35d8dde12a1d4dc4964dbaf4de766a538b98b
-  specs:
-    rack-jekyll (0.5.0)
-      jekyll (>= 1.3)
-      listen (>= 1.3)
-      rack (~> 2.0)
-
 GEM
   remote: https://rubygems.org/
   specs:
@@ -59,15 +50,10 @@ GEM
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     mercenary (0.4.0)
-    nio4r (2.5.9)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
     public_suffix (4.0.6)
-    puma (5.6.7)
-      nio4r (~> 2.0)
     pygments.rb (2.2.0)
-    rack (2.2.6.4)
-    rack-rewrite (1.5.1)
     rb-fsevent (0.10.4)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
@@ -97,11 +83,7 @@ DEPENDENCIES
   jekyll-sitemap
   kramdown (>= 2.3.0)
   kramdown-parser-gfm
-  puma
   pygments.rb
-  rack (~> 2.2)
-  rack-jekyll!
-  rack-rewrite
   stringex
   typogruby