docs: fix docstring formatting (#93)

* docs: fix docstring formatting

Committer: @parthea
PiperOrigin-RevId: 404756337

Source-Link: googleapis/googleapis@f034e5f

Source-Link: googleapis/googleapis-gen@8bb2d07
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google/cloud/artifactregistry_v1/types/artifact.py

@@ -25,14 +25,13 @@
 
 
 class DockerImage(proto.Message):
-    r"""DockerImage represents a docker artifact.
-    The following fields are returned as untyped metadata in the
-    Version resource, using camelcase keys (i.e.
-    metadata.imageSizeBytes):
-
-      - imageSizeBytes
-      - mediaType
-      - buildTime
+    r"""DockerImage represents a docker artifact. The following fields are
+    returned as untyped metadata in the Version resource, using
+    camelcase keys (i.e. metadata.imageSizeBytes):
+
+    -  imageSizeBytes
+    -  mediaType
+    -  buildTime
 
     Attributes:
         name (str):