Raise severity for System(Tx,Rx)PacketsDroppedTooHigh

Raise severity from warning to critical

Partial-Bug: PROD-15203
Change-Id: I32f19b5520bc200d61280da57f4ab5842b060454
diff --git a/linux/meta/prometheus.yml b/linux/meta/prometheus.yml
index df53426..0c66254 100644
--- a/linux/meta/prometheus.yml
+++ b/linux/meta/prometheus.yml
@@ -85,7 +85,7 @@
       if: rate(net_drop_in[1m]) > {{ net_rx_dropped_threshold }}
       {% raw %}
       labels:
-        severity: warning
+        severity: critical
         service: system
       annotations:
         summary: 'Too many received packets dropped on {{ $labels.host }} for interface {{ $labels.interface }}'
@@ -95,7 +95,7 @@
       if: rate(net_drop_out[1m]) > {{ net_tx_dropped_threshold }}
       {% raw %}
       labels:
-        severity: warning
+        severity: critical
         service: system
       annotations:
         summary: 'Too many transmitted packets dropped on {{ $labels.host }} for interface {{ $labels.interface }}'