Bump sinatra from 2.0.8.1 to 2.2.0

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]>

Gemfile.lock

@@ -83,7 +83,7 @@ GEM
     public_suffix (4.0.6)
     racc (1.6.0)
     rack (2.2.3)
-    rack-protection (2.0.8.1)
+    rack-protection (2.2.0)
       rack
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
@@ -122,17 +122,17 @@ GEM
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 1.4.0, < 1.7)
     ruby-progressbar (1.10.1)
-    ruby2_keywords (0.0.2)
+    ruby2_keywords (0.0.5)
     safe_yaml (1.0.5)
     simplecov (0.16.1)
       docile (~> 1.1)
       json (>= 1.8, < 3)
       simplecov-html (~> 0.10.0)
     simplecov-html (0.10.2)
-    sinatra (2.0.8.1)
+    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)
     sinatra-activerecord (2.0.14)
       activerecord (>= 3.2)