Merge pull request #374 from puppetlabs/bug-add_sync_to_puppet-lint-init

(bug) - Add synchronization to Dir.chdir in init_puppet_lint

Author: LukasAud

lib/puppet-languageserver/manifest/validation_provider.rb

@@ -109,7 +109,9 @@ def self.init_puppet_lint(root_dir, lint_options = [])
           linter_options = PuppetLint::OptParser.build
         else
           begin
-            Dir.chdir(root_dir.to_s) { linter_options = PuppetLint::OptParser.build }
+            $PuppetParserMutex.synchronize do # rubocop:disable Style/GlobalVars
+              Dir.chdir(root_dir.to_s) { linter_options = PuppetLint::OptParser.build }
+            end
           rescue OptionParser::InvalidOption => e
             PuppetLanguageServer.log_message(:error, "(#{name}) Error reading Puppet Lint configuration.  Using default: #{e}")
             linter_options = PuppetLint::OptParser.build