feat(spanner): update the api

#### spanner:v1

The following keys were added:
- schemas.KeyRangeInfo.properties.timeOffset (Total Keys: 2)

docs/dyn/spanner_v1.projects.instances.databases.html

@@ -455,6 +455,7 @@ <h3>Method Details</h3>
                         &quot;token&quot;: &quot;A String&quot;, # The token identifying the message, e.g. &#x27;METRIC_READ_CPU&#x27;. This should be unique within the service.
                       },
                       &quot;startKeyIndex&quot;: 42, # The index of the start key in indexed_keys.
+                      &quot;timeOffset&quot;: &quot;A String&quot;, # The time offset. This is the time since the start of the time interval.
                       &quot;unit&quot;: { # A message representing a user-facing string whose value may need to be translated before being displayed. # The unit of the metric. This is an unstructured field and will be mapped as is to the user.
                         &quot;args&quot;: { # A map of arguments used when creating the localized message. Keys represent parameter names which may be used by the localized version when substituting dynamic values.
                           &quot;a_key&quot;: &quot;A String&quot;,