Move `istio-ingressgateway` to Yorkie Namespace

[krapie]

What this PR does / why we need it:

Relocate the istio-ingressgateway to the yorkie namespace under the name yorkie-gateway.

The purpose of this move is to clearly segregate yorkie-related Kubernetes resources from other services for better organization and management.

Additionally, for production Istio deployments, it is crucial to separate the istio-ingressgateway and istiod components to enable independent operation.

In Istio, this gateway topology is called Dedicated application gateway.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

Additional documentation:

Checklist:

• [x] Added relevant tests or not required
• [x] Didn't break anything

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 50.95%. Comparing base (d5bc939) to head (50cddd9).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #836 +/- ## ======================================= Coverage 50.95% 50.95% ======================================= Files 70 70 Lines 10226 10226 ======================================= Hits 5211 5211 Misses 4487 4487 Partials 528 528 ```

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