Bump httparty in /examples/use-docker-ignore-gemfile-lock (#87)

Author: dependabot[bot]

examples/use-docker-ignore-gemfile-lock/Gemfile.lock

@@ -1,12 +1,10 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    httparty (0.18.1)
-      mime-types (~> 3.0)
+    httparty (0.21.0)
+      mini_mime (>= 1.0.0)
       multi_xml (>= 0.5.2)
-    mime-types (3.3.1)
-      mime-types-data (~> 3.2015)
-    mime-types-data (3.2020.1104)
+    mini_mime (1.1.5)
     multi_xml (0.6.0)
 
 PLATFORMS