Bump sinatra from 2.0.8.1 to 2.1.0

Bumps [sinatra](https://github.com/sinatra/sinatra) from 2.0.8.1 to 2.1.0.
- [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...v2.1.0)

Signed-off-by: dependabot[bot] <support@github.com>

Gemfile.lock

@@ -37,7 +37,7 @@ GEM
     puma (4.3.5)
       nio4r (~> 2.0)
     rack (2.2.3)
-    rack-protection (2.0.8.1)
+    rack-protection (2.1.0)
       rack
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
@@ -84,10 +84,10 @@ GEM
       json (>= 1.8, < 3)
       simplecov-html (~> 0.10.0)
     simplecov-html (0.10.2)
-    sinatra (2.0.8.1)
+    sinatra (2.1.0)
       mustermann (~> 1.0)
-      rack (~> 2.0)
-      rack-protection (= 2.0.8.1)
+      rack (~> 2.2)
+      rack-protection (= 2.1.0)
       tilt (~> 2.0)
     strptime (0.2.4)
     sync (0.5.0)