add empty as null on time series

Author: markov00

x-pack/plugins/security_solution/public/common/components/visualization_actions/lens_attributes/common/alerts/alerts_histogram.ts

@@ -80,6 +80,7 @@ export const getAlertsHistogramLensAttributes: GetLensAttributes = (
                   isBucketed: false,
                   scale: 'ratio',
                   sourceField: '___records___',
+                  params: { emptyAsNull: true },
                 },
                 '34919782-4546-43a5-b668-06ac934d3acd': {
                   label: `Top values of ${stackByField}`,

x-pack/plugins/security_solution/public/common/components/visualization_actions/lens_attributes/common/events.ts

@@ -81,6 +81,7 @@ export const getEventsHistogramLensAttributes: GetLensAttributes = (
                   isBucketed: false,
                   scale: 'ratio',
                   sourceField: '___records___',
+                  params: { emptyAsNull: true },
                 },
                 '34919782-4546-43a5-b668-06ac934d3acd': {
                   label: `Top values of ${stackByField}`,

x-pack/plugins/security_solution/public/common/components/visualization_actions/lens_attributes/common/external_alert.ts

@@ -101,6 +101,7 @@ export const getExternalAlertLensAttributes: GetLensAttributes = (
                   isBucketed: false,
                   scale: 'ratio',
                   sourceField: '___records___',
+                  params: { emptyAsNull: true },
                 },
                 '42334c6e-98d9-47a2-b4cb-a445abb44c93': {
                   label: TOP_VALUE(`${stackByField}`), // could be event.category

x-pack/plugins/security_solution/public/common/components/visualization_actions/lens_attributes/network/dns_top_domains.ts

@@ -143,6 +143,7 @@ export const getDnsTopDomainsLensAttributes: GetLensAttributes = (
                   scale: 'ratio',
                   sourceField: 'dns.question.name',
                   isBucketed: false,
+                  params: { emptyAsNull: true },
                 },
               },
               columnOrder: [