Run bundle update to use latest versions of gems. (#38)

Addresses security alert for Rack 2.0.5

Author: danj-stripe

Gemfile.lock

@@ -4,12 +4,12 @@ GEM
     dotenv (2.2.1)
     encrypted_cookie (0.0.5)
       rack (>= 1.1, < 3)
-    faraday (0.15.2)
+    faraday (0.15.3)
       multipart-post (>= 1.2, < 3)
     json (2.1.0)
     multipart-post (2.0.0)
-    mustermann (1.0.2)
-    rack (2.0.5)
+    mustermann (1.0.3)
+    rack (2.0.6)
     rack-protection (2.0.2)
       rack
     sinatra (2.0.2)