Update sinatra to version 2.2.0

Author: depfu[bot]

Gemfile.lock

@@ -227,7 +227,7 @@ GEM
       sinatra
     racc (1.5.2)
     rack (2.2.3)
-    rack-protection (2.1.0)
+    rack-protection (2.2.0)
       rack
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
@@ -266,18 +266,18 @@ GEM
       railties (>= 5.0)
     rexml (3.2.5)
     ruby-progressbar (1.11.0)
-    ruby2_keywords (0.0.2)
+    ruby2_keywords (0.0.5)
     rubyzip (2.3.0)
     simplecov (0.21.2)
       docile (~> 1.1)
       simplecov-html (~> 0.11)
       simplecov_json_formatter (~> 0.1)
     simplecov-html (0.12.3)
     simplecov_json_formatter (0.1.2)
-    sinatra (2.1.0)
+    sinatra (2.2.0)
       mustermann (~> 1.0)
       rack (~> 2.2)
-      rack-protection (= 2.1.0)
+      rack-protection (= 2.2.0)
       tilt (~> 2.0)
     sprockets (4.0.2)
       concurrent-ruby (~> 1.0)