Gracefully handle OS_TENANT_NAME

If OS_TENANT_NAME is not defined but OS_PROJECT_NAME is defined, quietly
set OS_TENANT_NAME=OS_PROJECT_NAME as to not just fail. Since quickstart
relies on os_tenant_name all over the place but the newer clouds are
Keystone v3 which does not require os_tenant_name, let's not have the
reproducer just fail if we can gracefully continue.

Change-Id: Ie508c7a9723f6eca3616c9b6b5b6795582a8c121
Related-Bug: #1750455

roles/create-reproducer-script/templates/reproducer-quickstart.sh.j2

@@ -43,8 +43,13 @@ set -e
 
 # Check that tenant credentials have been sourced
 if [[ ! -v OS_TENANT_NAME ]]; then
-    echo "Tenant credentials are not sourced."
-    exit 1;
+    # TODO(aschultz): work around for LP#1750455
+    if [[ -v OS_PROJECT_NAME ]]; then
+        export OS_TENANT_NAME=$OS_PROJECT_NAME
+    else
+        echo "Tenant credentials are not sourced."
+        exit 1;
+    fi
 fi
 
 # Input argument assignments