Edit Monitoring API required/optional/flattening (#162)

* Edit Monitoring API required/optional/flattening

Updates the GAPIC config based on proto comments.

google/monitoring/v3/monitoring_gapic.yaml

@@ -72,11 +72,9 @@ interfaces:
       - parameters:
         - name
         - group
-        - validate_only
     required_fields:
     - name
     - group
-    - validate_only
     request_object_method: true
     retry_codes_name: non_idempotent
     retry_params_name: default
@@ -88,10 +86,8 @@ interfaces:
       groups:
       - parameters:
         - group
-        - validate_only
     required_fields:
     - group
-    - validate_only
     request_object_method: true
     retry_codes_name: idempotent
     retry_params_name: default
@@ -116,12 +112,8 @@ interfaces:
       groups:
       - parameters:
         - name
-        - filter
-        - interval
     required_fields:
     - name
-    - filter
-    - interval
     request_object_method: true
     page_streaming:
       request:
@@ -165,10 +157,8 @@ interfaces:
       groups:
       - parameters:
         - name
-        - filter
     required_fields:
     - name
-    - filter
     request_object_method: true
     page_streaming:
       request:
@@ -200,10 +190,8 @@ interfaces:
       groups:
       - parameters:
         - name
-        - filter
     required_fields:
     - name
-    - filter
     request_object_method: true
     page_streaming:
       request:
@@ -259,12 +247,17 @@ interfaces:
       name: metric_descriptor_path
     timeout_millis: 60000
   - name: ListTimeSeries
+    flattening:
+      groups:
+      - parameters:
+        - name
+        - filter
+        - interval
+        - view
     required_fields:
     - name
     - filter
     - interval
-    - aggregation
-    - order_by
     - view
     request_object_method: true
     page_streaming: