add GlobalEndpoint

[akwan224]

Description of changes:
Following up with the launch of global cluster endpoints https://aws.amazon.com/about-aws/whats-new/2024/10/amazon-aurora-global-database-writer-endpoint, adding global cluster endpoints to rds-global-cluster

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[Dmytrok-amz]

The build is failing with checkstyle issues:

Trim Trailing Whitespace.................................................Failed

- hook id: trailing-whitespace

- exit code: 1

- files were modified by this hook
...

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Error: Process completed with exit code 1.

[Dmytrok-amz]

LGTM - pending build verification

[cwoolum]

@Dmytrok-amz , can we get this merged in?

[kcwinner]

aws-cloudformation/cloudformation-coverage-roadmap#2364

[dbayardAWS]

I think line 75 of aws-rds-globalcluster/aws-rds-globalcluster.json is supposed to say "readOnlyProperties" as the tag, but it says "readOnly".