Update Helm release base to v1.19.3

This MR contains the following updates:

Package	Update	Change
base	patch	1.19.1 -> 1.19.3

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Release Notes

istio/istio (base)

v1.19.3: Istio 1.19.3

Artifacts Release Notes

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever MR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this MR and you won't be reminded about this update again.

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