feat(rds): RDS for SQL Server 16 without a specific minor version (#2…

…8615)

This PR supports version 16 for RDS for SQL Server without a specific minor version.

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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*

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

@@ -1975,6 +1975,9 @@ export class SqlServerEngineVersion {
   public static readonly VER_15_00_4335_1_V1 = SqlServerEngineVersion.of('15.00.4335.1.v1', '15.00');
   /** Version "15.00.4345.5.v1". */
   public static readonly VER_15_00_4345_5_V1 = SqlServerEngineVersion.of('15.00.4345.5.v1', '15.00');
+
+  /** Version "16.00" (only a major version, without a specific minor version). */
+  public static readonly VER_16 = SqlServerEngineVersion.of('16.00', '16.00');
   /** Version "16.00.4085.2.v1". */
   public static readonly VER_16_00_4085_2_V1 = SqlServerEngineVersion.of('16.00.4085.2.v1', '16.00');
   /** Version "16.00.4095.4.v1". */