Bump gems, default puppet version, and gemspec

Notably, simplecov was pinned at an old version and I had a lot of
trouble building it.

Author: ahayworth

config/puppet-versions.json

@@ -17,13 +17,16 @@
   {
     "minimum_version": "5.0.0",
     "maximum_version": "5.99.99",
-    "additional_gems": [
-    ]
+    "additional_gems": []
   },
   {
     "minimum_version": "6.0.0",
     "maximum_version": "6.99.99",
-    "additional_gems": [
-    ]
+    "additional_gems": []
+  },
+  {
+    "minimum_version": "7.0.0",
+    "maximum_version": "7.99.99",
+    "additional_gems": []
   }
 ]

octocatalog-diff.gemspec

@@ -1,6 +1,6 @@
 require 'json'
 
-DEFAULT_PUPPET_VERSION = '5.5.8'.freeze
+DEFAULT_PUPPET_VERSION = '5.5.22'.freeze
 
 Gem::Specification.new do |s|
   s.required_ruby_version = '>= 2.0.0'
@@ -37,8 +37,8 @@ EOF
 
   s.add_development_dependency 'rubocop', '= 0.48.1'
 
-  s.add_development_dependency 'simplecov', '~> 0.14.1'
-  s.add_development_dependency 'simplecov-erb', '~> 0.1.1'
+  s.add_development_dependency 'simplecov', '~> 0.17.0'
+  s.add_development_dependency 'simplecov-erb', '~> 1.0.0'
 
   puppet_version = ENV['PUPPET_VERSION'] || DEFAULT_PUPPET_VERSION
   s.add_development_dependency 'puppet', "~> #{puppet_version}"