feat: Add relevant attribute descriptions where available (step 1) (google-api-php-client-services#4591)

Author: razvanphp

generator/src/googleapis/codegen/languages/php/default/templates/___api_className___/___models_className___.php.tmpl

@@ -28,6 +28,14 @@ class {{ model.className }} extends {% if model.superClass %}{{ model.superClass
  {% else %}
  {% if property.annotationType %}
   /**
+{% if property.description %}
+  {% if property.description %}
+  {% filter block_comment %}
+   * {{ property.description }}
+  {% endfilter %}
+   *
+  {% endif %}
+{% endif %}
    * @var {{ property.annotationType }}{% if property.dataType == "array" or property.dataType == "map" %}[]{% endif %}
    */
  {% endif %}

generator/tests/testdata/golden/php/default/kitchen_sink.golden

@@ -747,6 +747,8 @@ namespace Google\Service\KitchSink;
 class Enum extends \Google\Model
 {
   /**
+   * Enum type name.
+   *
    * @var string
    */
   public $name;
@@ -991,6 +993,8 @@ namespace Google\Service\KitchSink;
 class KitchSinkReadOnly extends \Google\Model
 {
   /**
+   * ReadOnly type name.
+   *
    * @var string
    */
   public $name;
@@ -3351,10 +3355,14 @@ class SubmissionAttribution extends \Google\Model
         "object" => "$object",
   ];
   /**
+   * A member with a $ in the name
+   *
    * @var string
    */
   public $avatarUrl;
   /**
+   * A member with a $ in the name, but if you strip it, you get a reserved word
+   *
    * @var string
    */
   public $object;