Use versioned endpoint in ec2authtoken/auth_uri

The option doesn't support version discovery,
so set it explicitly.

Change-Id: I986ea620050f267d020dc51476039cb076f65840
Related-Prod: PROD-19828
diff --git a/heat/files/pike/heat.conf.Debian b/heat/files/pike/heat.conf.Debian
index d69231f..95db173 100644
--- a/heat/files/pike/heat.conf.Debian
+++ b/heat/files/pike/heat.conf.Debian
@@ -1299,7 +1299,8 @@
 #
 
 # Authentication Endpoint URI. (string value)
-auth_uri={{ server.identity.get('protocol', 'http') }}://{{ server.identity.host }}:5000
+# NOTE(vsaienko) autodiscovery doesn't work here. Set version explicitly
+auth_uri={{ server.identity.get('protocol', 'http') }}://{{ server.identity.host }}:5000/v3
 
 # Allow orchestration of multiple clouds. (boolean value)
 #multi_cloud=false
diff --git a/heat/files/queens/heat.conf.Debian b/heat/files/queens/heat.conf.Debian
index 8051e79..a392c59 100644
--- a/heat/files/queens/heat.conf.Debian
+++ b/heat/files/queens/heat.conf.Debian
@@ -868,7 +868,8 @@
 
 # Authentication Endpoint URI. (string value)
 #auth_uri = <None>
-auth_uri = {{ server.identity.get('protocol', 'http') }}://{{ server.identity.host }}:5000
+# NOTE(vsaienko) autodiscovery doesn't work here. Set version explicitly
+auth_uri = {{ server.identity.get('protocol', 'http') }}://{{ server.identity.host }}:5000/v3
 
 # Allow orchestration of multiple clouds. (boolean value)
 #multi_cloud = false