(CAT-1669) - Add trailing comma to completion item

Prior to this commit, we would return completion items to vscode without
a trailing comma. A trailing comma is the suggested style as per the
puppet code docs, so we should append this to the returned value.

Author: jordanbreen28

lib/puppet-languageserver/manifest/completion_provider.rb

@@ -291,7 +291,7 @@ def self.resolve(session_state, completion_item)
           unless param_type.nil?
             # TODO: More things?
             result.documentation = param_type[:doc] unless param_type[:doc].nil?
-            result.insertText = "#{data['param']} => "
+            result.insertText = "#{data['param']} => ,"
           end
         when 'resource_property'
           item_type = PuppetLanguageServer::PuppetHelper.get_type(session_state, data['resource_type'])
@@ -301,7 +301,7 @@ def self.resolve(session_state, completion_item)
           unless prop_type.nil?
             # TODO: More things?
             result.documentation = prop_type[:doc] unless prop_type[:doc].nil?
-            result.insertText = "#{data['prop']} => "
+            result.insertText = "#{data['prop']} => ,"
           end
 
         when 'resource_class'
@@ -320,7 +320,7 @@ def self.resolve(session_state, completion_item)
             doc += param_type[:type] unless param_type[:type].nil?
             doc += "---\n#{param_type[:doc]}" unless param_type[:doc].nil?
             result.documentation = doc
-            result.insertText = "#{data['param']} => "
+            result.insertText = "#{data['param']} => ,"
           end
         end