Force pry to 0.12 so that it works well with pry-byebug 3.7

Gemfile

@@ -149,6 +149,7 @@ group :development do
   gem 'byebug', '~> 11.0' # 11.1 requires ruby 2.4
   gem 'debugger-linecache'
   gem "newrelic_rpm", "~> 3.0"
+  gem "pry", "~> 0.12.0" # pry 0.13 is not compatible with pry-byebug 3.7
   gem 'pry-byebug', '~> 3.7' # 3.8 requires ruby 2.4
   gem 'rubocop'
   gem 'rubocop-rails'

Gemfile.lock

@@ -446,7 +446,7 @@ GEM
     mail (2.5.5)
       mime-types (~> 1.16)
       treetop (~> 1.4.8)
-    method_source (1.0.0)
+    method_source (0.9.2)
     mime-types (1.25.1)
     mini_mime (1.0.1)
     mini_portile2 (2.4.0)
@@ -495,9 +495,9 @@ GEM
       activerecord (~> 3.0)
     polyglot (0.3.5)
     power_assert (1.1.5)
-    pry (0.13.1)
-      coderay (~> 1.1)
-      method_source (~> 1.0)
+    pry (0.12.2)
+      coderay (~> 1.1.0)
+      method_source (~> 0.9.0)
     pry-byebug (3.7.0)
       byebug (~> 11.0)
       pry (~> 0.10)
@@ -750,6 +750,7 @@ DEPENDENCIES
   paper_trail (~> 5.2.3)
   paperclip (~> 3.4.1)
   pg (~> 0.21.0)
+  pry (~> 0.12.0)
   pry-byebug (~> 3.7)
   rack-mini-profiler (< 3.0.0)
   rack-rewrite