[yarn] Set name_version when version is not specified (#62348)

* Set name_version when version is not specified, fix #55097

This will default to installing the latest version available

* Add changelog fragment

* update changelog

changelogs/fragments/62348-yarn-no_version_install_fix.yml

@@ -0,0 +1,3 @@
+---
+bugfixes:
+  - yarn - handle no version when installing module by name (https://github.com/ansible/ansible/issues/55097)

lib/ansible/modules/packaging/language/yarn.py

@@ -183,6 +183,8 @@ class Yarn(object):
 
         if kwargs['version'] and self.name is not None:
             self.name_version = self.name + '@' + str(self.version)
+        elif self.name is not None:
+            self.name_version = self.name
 
     def _exec(self, args, run_in_check_mode=False, check_rc=True):
         if not self.module.check_mode or (self.module.check_mode and run_in_check_mode):