feat: Added an update to CoreDNS

[DannyLiCom]

Fixes / Features

Enhance DNS Scalability for Large-Scale Testing:

• Issue: During large-scale load testing, the existing Kube-DNS solution was found to be insufficient in supporting the demands of McJAX and Pathways TPU paths, leading to potential performance bottlenecks.
• Solution: Adjusted configurations to default to CoreDNS for McJAX and Pathways TPU paths.

Testing / Documentation

When using the command python3 xpk.py cluster create-pathways to create a cluster, CoreDNS will be used by default. For the general command python3 xpk.py cluster create, kube-dns is still the default.

• [ y/n ] Tests pass
• [ y/n ] Appropriate changes to documentation are included in the PR

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[ycchenzheng]

@SujeethJinesh

[SujeethJinesh]

Thanks Danny!

[SujeethJinesh]

Thanks Danny!

I also think one more thing we should do is add a unit test for this addition. Though it seems like there are very few set up standards for this. Maybe @pawloch00 or others can chime in on where best to create the unit tests.

https://github.com/AI-Hypercomputer/xpk/tree/develop/src/xpk/core/tests/unit

[pawloch00]

Did testing scenarions included only TPU clusters? What with clusters created with GPUs, especially A3 Mega or ultra, that are created using cluster toolkit?

[SujeethJinesh]

LGTM from my perspective, but I'm not an XPK owner, so best to get verification from @Obliviour or @pawloch00

[DannyLiCom]

@pawloch00 please review this PR again

[pawloch00]

Please ignore integration tests failing for now. I will try to fix it and let you know

[DannyLiCom]

Okay, Thanks!

[pawloch00]

Okay, Thanks!

Please accept collaborator invitation and rerun the tests