Remove basic auth between promtail chart and loki

The promtail chart is anyway configured to use the Loki service for
pushing logs. The service itself is not password protected and this
was thus not required.

Change-Id: I886b76ca7e5d6e8af370a2cd0f527892008c7600
diff --git a/charts/promtail/promtail.yaml b/charts/promtail/promtail.yaml
index 8021291..b3adf2b 100644
--- a/charts/promtail/promtail.yaml
+++ b/charts/promtail/promtail.yaml
@@ -28,8 +28,8 @@
   serviceName: #@ "loki-{}".format(data.values.namespace)
   servicePort: 3100
   serviceScheme: http
-  user: #@ data.values.logging.loki.username
-  password: #@ data.values.logging.loki.password
+  user:
+  password:
 
 nameOverride: #@ "promtail-{}".format(data.values.namespace, data.values.namespace)