chore(ec2): add-m9g-instance-class (#36339)

### Issue # (if applicable)

Closes #36320

### Reason for this change

Added new graviton 5 instance class

### Description of changes

Updated the ec2 instance class enum definitions to include new graviton 5 type

### Describe any new or updated permissions being added

None


### Checklist
- [ ] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: matoom-nomu

packages/aws-cdk-lib/aws-ec2/lib/instance-types.ts

@@ -1487,6 +1487,16 @@ export enum InstanceClass {
    */
   M8A = 'm8a',
 
+  /**
+   * Standard instances, 9th generation with Graviton5 processors
+   */
+  STANDARD9_GRAVITON = 'standard9-graviton',
+
+  /**
+   * Standard instances, 9th generation with Graviton5 processors
+   */
+  M9G = 'm9g',
+
   /**
    * High memory and compute capacity instances, 1st generation
    */
@@ -2095,6 +2105,8 @@ export class InstanceType {
       [InstanceClass.M7A]: 'm7a',
       [InstanceClass.STANDARD8_AMD]: 'm8a',
       [InstanceClass.M8A]: 'm8a',
+      [InstanceClass.STANDARD9_GRAVITON]: 'm9g',
+      [InstanceClass.M9G]: 'm9g',
       [InstanceClass.HIGH_COMPUTE_MEMORY1]: 'z1d',
       [InstanceClass.Z1D]: 'z1d',
       [InstanceClass.INFERENCE1]: 'inf1',