Bump sinatra from 2.0.8.1 to 2.2.0 in /ruby

Bumps [sinatra](https://github.com/sinatra/sinatra) from 2.0.8.1 to 2.2.0.
- [Release notes](https://github.com/sinatra/sinatra/releases)
- [Changelog](https://github.com/sinatra/sinatra/blob/master/CHANGELOG.md)
- [Commits](sinatra/sinatra@v2.0.8.1...v2.2.0)

---
updated-dependencies:
- dependency-name: sinatra
  dependency-type: direct:production
...

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

ruby/Gemfile.lock

@@ -8,20 +8,20 @@ GEM
       ruby2_keywords
     faraday-net_http (1.0.1)
     multipart-post (2.2.3)
-    mustermann (1.1.1)
+    mustermann (1.1.2)
       ruby2_keywords (~> 0.0.1)
     plaid (14.10.0)
       faraday (~> 1.0, >= 1.0.1)
     rack (2.2.4)
-    rack-protection (2.0.8.1)
+    rack-protection (2.2.0)
       rack
-    ruby2_keywords (0.0.2)
-    sinatra (2.0.8.1)
+    ruby2_keywords (0.0.5)
+    sinatra (2.2.0)
       mustermann (~> 1.0)
-      rack (~> 2.0)
-      rack-protection (= 2.0.8.1)
+      rack (~> 2.2)
+      rack-protection (= 2.2.0)
       tilt (~> 2.0)
-    tilt (2.0.10)
+    tilt (2.0.11)
 
 PLATFORMS
   ruby