(MODULES-10661) Add OS X 10.15 support

Author: GabrielNagy

metadata.json

@@ -108,7 +108,9 @@
       "operatingsystem": "OSX",
       "operatingsystemrelease": [
         "10.12",
-        "10.13"
+        "10.13",
+        "10.14",
+        "10.15"
        ]
     }
   ],

spec/classes/puppet_agent_osfamily_darwin_spec.rb

@@ -30,7 +30,7 @@
   describe 'supported environment' do
     let(:params) {{ package_version: package_version }}
     context "when running a supported OSX" do
-      ["osx-10.12-x86_64", "osx-10.13-x86_64", "osx-10.14-x86_64"].each do |tag|
+      ["osx-10.12-x86_64", "osx-10.13-x86_64", "osx-10.14-x86_64", "osx-10.15-x86_64"].each do |tag|
         context "on #{tag} with no aio_version" do
           let(:osmajor) { tag.split('-')[1] }