feat(monitoring): update the api

#### monitoring:v1

The following keys were added:
- schemas.DataSet.properties.targetAxis.type (Total Keys: 1)
- schemas.Threshold.properties.targetAxis.type (Total Keys: 1)
- schemas.XyChart.properties.y2Axis.$ref (Total Keys: 1)

docs/dyn/monitoring_v1.locations.global_.metricsScopes.html

@@ -84,7 +84,7 @@ <h2>Instance Methods</h2>
 <p class="firstline">Close httplib2 connections.</p>
 <p class="toc_element">
   <code><a href="#get">get(name, x__xgafv=None)</a></code></p>
-<p class="firstline">Returns a specific Metrics Scope.</p>
+<p class="firstline">Returns a specific Metrics Scope, including the list of projects monitored by the specified Metrics Scope.</p>
 <p class="toc_element">
   <code><a href="#listMetricsScopesByMonitoredProject">listMetricsScopesByMonitoredProject(monitoredResourceContainer=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Returns a list of every Metrics Scope that a specific MonitoredProject has been added to. The metrics scope representing the specified monitored project will always be the first entry in the response.</p>
@@ -96,7 +96,7 @@ <h3>Method Details</h3>
 
 <div class="method">
     <code class="details" id="get">get(name, x__xgafv=None)</code>
-  <pre>Returns a specific Metrics Scope.
+  <pre>Returns a specific Metrics Scope, including the list of projects monitored by the specified Metrics Scope.
 
 Args:
   name: string, Required. The resource name of the Metrics Scope. Example: locations/global/metricsScopes/{SCOPING_PROJECT_ID_OR_NUMBER} (required)