Add cinder database connection parameters

[database]
idle_timeout
max_pool_size
max_retries
max_overflow

Change-Id: I6fac03a5616678ae99a1ed95fd40e34b47685ae8
Related-prod: PROD-26294
diff --git a/tests/pillar/volume_single.sls b/tests/pillar/volume_single.sls
index 086fbfd..cea5f55 100644
--- a/tests/pillar/volume_single.sls
+++ b/tests/pillar/volume_single.sls
@@ -21,6 +21,10 @@
       name: cinder
       user: cinder
       password: password
+      idle_timeout: 280
+      max_pool_size: 30
+      max_retries: '-1'
+      max_overflow: 40
     identity:
       engine: keystone
       host: 127.0.0.1