feat: add FATAL log level (#80)

Customer request to add FATAL into the log levels. Does not have impact in this library but it is needed in our internal facade.

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_By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license_

Author: voho

API.md

@@ -46447,6 +46447,7 @@ Level of a given log.
 | --- | --- |
 | <code><a href="#cdk-monitoring-constructs.LogLevel.ERROR">ERROR</a></code> | *No description.* |
 | <code><a href="#cdk-monitoring-constructs.LogLevel.CRITICAL">CRITICAL</a></code> | *No description.* |
+| <code><a href="#cdk-monitoring-constructs.LogLevel.FATAL">FATAL</a></code> | *No description.* |
 
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@@ -46460,6 +46461,11 @@ Level of a given log.
 ---
 
 
+##### `FATAL` <a name="FATAL" id="cdk-monitoring-constructs.LogLevel.FATAL"></a>
+
+---
+
+
 ### MetricStatistic <a name="MetricStatistic" id="cdk-monitoring-constructs.MetricStatistic"></a>
 
 Metric aggregation statistic to be used with the IMetric objects.

lib/common/monitoring/alarms/LogLevelAlarmFactory.ts

@@ -9,6 +9,7 @@ import { MetricWithAlarmSupport } from "../../metric";
 export enum LogLevel {
   ERROR = "ERROR",
   CRITICAL = "CRITICAL",
+  FATAL = "FATAL",
 }
 
 export interface LogLevelCountThreshold extends CustomAlarmThreshold {