Renovate: Istio-gateway Update to 1.25.3

This MR contains the following updates:

Package	Update	Change
istiod	minor	1.25.2 -> 1.25.3

Complete MR checklist

Assignee

• Followed upgrade instructions outlined in docs/DEVELOPMENT_MAINTENANCE.md
• Update Docs with new/updated steps as needed
• Tested and Validated Changes made with supporting info like logs or screenshots from test pipelines
  • Tested clean install on k3d dev cluster
  • Tested upgrade from 1.25.2 to 1.25.3
  • Tested SSO with local Keycloak enabled deployment
  • Migration test from Operator 1.23.6 to Operator-less 1.25.3
  • BB Test Pipeline

Successful upgrade of Istio O-L packages in k3d dev test cluster

% helm history -n bigbang istio-crds && helm history -n bigbang istiod && helm history -n bigbang public-ingressgateway 
REVISION	UPDATED                 	STATUS    	CHART                 	APP VERSION	DESCRIPTION     
1       	Thu May 22 17:28:20 2025	superseded	istio-crds-1.25.2-bb.0	1.25.2     	Install complete
2       	Thu May 22 17:35:50 2025	deployed  	istio-crds-1.25.3-bb.0	1.25.3     	Upgrade complete
REVISION	UPDATED                 	STATUS    	CHART             	APP VERSION	DESCRIPTION     
1       	Thu May 22 17:28:50 2025	superseded	istiod-1.25.2-bb.4	1.25.2     	Install complete
2       	Thu May 22 17:36:07 2025	deployed  	istiod-1.25.3-bb.0	1.25.3     	Upgrade complete
REVISION	UPDATED                 	STATUS    	CHART              	APP VERSION	DESCRIPTION     
1       	Thu May 22 17:29:20 2025	superseded	gateway-1.25.2-bb.1	1.25.2     	Install complete
2       	Thu May 22 17:35:49 2025	deployed  	gateway-1.25.3-bb.0	1.25.3     	Upgrade complete

Reviewer only

• Tested and Validated changes

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Configuration

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Upgrade Notices

N/A