docs: Update property requirement specifications (#470)

* docs: Update property requirement specifications PiperOrigin-RevId: 557861399 Source-Link: googleapis/googleapis@3303b93 Source-Link: googleapis/googleapis-gen@fb0d0a4 Copy-Tag: eyJwIjoiLmdpdGh1Yi8uT3dsQm90LnlhbWwiLCJoIjoiZmIwZDBhNDUzODVlYjBiZTU4NDIxMTFhZjc5YWY1ZDcxOWQzMjE2OCJ9 * 🦉 Updates from OwlBot post-processor See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md * apply docs fix from googleapis/gapic-generator-python#1721 --------- Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com> Co-authored-by: Anthonios Partheniou <partheniou@google.com>

Author: gcf-owl-bot[bot]

google/cloud/datastore_v1/types/query.py

@@ -455,9 +455,13 @@ class PropertyReference(proto.Message):
 
  Attributes:
  name (str):
- The name of the property.
- If name includes "."s, it may be interpreted as
- a property name path.
+ A reference to a property.
+
+ Requires:
+
+ - MUST be a dot-delimited (``.``) string of segments, where
+ each segment conforms to [entity property
+ name][google.datastore.v1.Entity.properties] limitations.
  """
 
  name: str = proto.Field(