Add Gateway API v1.3 Blog Post (#50999)

* Add Gateway API v1.3 Blog Post
Add Gateway API v1.3 Blog Post for 05-22-2025

* Changes added per review comments.

* Add further review changes

Co-authored-by: dipesh-rawat
Co-authored-by: Hii-arpit

* Update content/en/blog/_posts/2025-05-22-gateway-api-v1.3/index.md

Co-authored-by: Dipesh Rawat

* Update content/en/blog/_posts/2025-05-22-gateway-api-v1.3/index.md

Co-authored-by: Rob Scott

* Add changes requested by Rob Scott

Co-authored-by: robscott

* Further changes suggested by Rob Scott

Co-authored-by: robscott

* Update content/en/blog/_posts/2025-05-28-gateway-api-v1.3/index.md

Co-authored-by: Tim Bannister

* Update content/en/blog/_posts/2025-05-28-gateway-api-v1.3/index.md

Co-authored-by: Tim Bannister

* Update content/en/blog/_posts/2025-05-28-gateway-api-v1.3/index.md

Co-authored-by: Tim Bannister

* Apply suggestions from code review

Co-authored-by: Tim Bannister

* Apply suggestions from code review

Co-authored-by: Tim Bannister

* Apply suggestions from code review

Co-authored-by: Tim Bannister, Eric Bishop

* Address final review comments

Co-authored-by: lmktfy, nickyoung

* Align article front matter and filename

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Co-authored-by: Tim Bannister <[email protected]>

Author: candita