Add gae_instance resources to testdata for metrics_proto_api_test.

testdata/Resources/in.txt

@@ -121,3 +121,21 @@ labels: <
   key: "k8s.pod.name"
   value: "pod1"
 >
+---
+type: "gae_instance"
+labels: <
+  key: "appengine.service.id"
+  value: "default"
+>
+labels: <
+  key: "appengine.version.id"
+  value: "version1"
+>
+labels: <
+  key: "appengine.instance.id"
+  value: "inst1"
+>
+labels: <
+  key: "cloud.region"
+  value: "region1"
+>

testdata/Resources/out.txt

@@ -77,4 +77,21 @@ labels: <
 >
 ---
 type: "global"
-
+---
+type: "gae_instance"
+labels: <
+  key: "module_id"
+  value: "default"
+>
+labels: <
+  key: "version_id"
+  value: "version1"
+>
+labels: <
+  key: "instance_id"
+  value: "inst1"
+>
+labels: <
+  key: "location"
+  value: "region1"
+>

testdata/ResourcesWithMissingFields/in.txt

@@ -121,3 +121,22 @@ labels: <
   key: "k8s.pod.name"
   value: "pod1"
 >
+---
+type: "gae_instance"
+#labels: <
+#  key: "appengine.service.id"
+#  value: "default"
+#>
+labels: <
+  key: "appengine.version.id"
+  value: "version1"
+>
+labels: <
+  key: "appengine.instance.id"
+  value: "inst1"
+>
+labels: <
+  key: "cloud.region"
+  value: "region1"
+>
+

testdata/ResourcesWithMissingFields/out.txt

@@ -9,4 +9,5 @@ type: "global"
 type: "global"
 ---
 type: "global"
-
+---
+type: "global"