fix(rds): Add missing Aurora engine 8.0.mysql_aurora.3.02.3 (#26462)

Add missing Aurora Engine Version 3_02_3. 
See Aurora docs at https://docs.aws.amazon.com/AmazonRDS/latest/AuroraMySQLReleaseNotes/AuroraMySQL.Updates.3023.html

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packages/aws-cdk-lib/aws-rds/lib/cluster-engine.ts

@@ -430,6 +430,8 @@ export class AuroraMysqlEngineVersion {
   public static readonly VER_3_02_1 = AuroraMysqlEngineVersion.builtIn_8_0('3.02.1');
   /** Version "8.0.mysql_aurora.3.02.2". */
   public static readonly VER_3_02_2 = AuroraMysqlEngineVersion.builtIn_8_0('3.02.2');
+  /** Version "8.0.mysql_aurora.3.02.3". */
+  public static readonly VER_3_02_3 = AuroraMysqlEngineVersion.builtIn_8_0('3.02.3');
   /** Version "8.0.mysql_aurora.3.03.0". */
   public static readonly VER_3_03_0 = AuroraMysqlEngineVersion.builtIn_8_0('3.03.0');