Fix heat/meta/prometheus.yml for the CI

Change-Id: I297d6b0f24f138b32e513acaf49c3f11a0c2afba
diff --git a/heat/map.jinja b/heat/map.jinja
index f6c7a9f..1a40ab9 100644
--- a/heat/map.jinja
+++ b/heat/map.jinja
@@ -22,3 +22,9 @@
         'pkgs': ['python-heatclient'],
     },
 }, merge=pillar.heat.get('client', {})) %}
+
+{% set monitoring = salt['grains.filter_by']({
+    'default': {
+        'error_log_rate': 0.2,
+    },
+}, grain='os_family', merge=salt['pillar.get']('heat:monitoring')) %}
diff --git a/heat/meta/prometheus.yml b/heat/meta/prometheus.yml
index dc3d01c..5155e72 100644
--- a/heat/meta/prometheus.yml
+++ b/heat/meta/prometheus.yml
@@ -1,6 +1,6 @@
 {%- if pillar.heat.server is defined %}
 
-{%- from "heat/map.jinja" import server with context %}
+{%- from "heat/map.jinja" import server, monitoring with context %}
 {%- if server.get('enabled', False) %}
 {% raw %}
 server:
@@ -18,7 +18,7 @@
             Endpoint check for '{{ $labels.service }}' is down for 2 minutes
     HeatErrorLogsTooHigh:
 {%- endraw %}
-      {%- set log_threshold = prometheus_server.get('alert', {}).get('HeatErrorLogsTooHigh', {}).get('var', {}).get('threshold', 0.2 ) %}
+      {%- set log_threshold = monitoring.error_log_rate|float %}
       if: >-
         sum(rate(log_messages{service="heat",level=~"error|emergency|fatal"}[5m])) without (level) > {{ log_threshold }}
 {%- raw %}