Merge pull request #804 from puppetlabs/CAT-1692-compatibility-fix

(CAT-1692) - Compatibility fix with puppet 7.14

Author: Ramesh7

lib/puppet/type/concat_file.rb

@@ -297,7 +297,7 @@ def nested_merge(hash1, hash2)
   def fragment_content(r)
     if r[:content].nil? == false
       # Explicitly resolve deferred values.
-      fragment_content = r[:content].instance_of?(Puppet::Pops::Evaluator::DeferredValue) ? r[:content].resolve : r[:content]
+      fragment_content = r[:content].respond_to?(:resolve) ? r[:content].resolve : r[:content]
     elsif r[:source].nil? == false
       @source = nil
       Array(r[:source]).each do |source|