test(e2e): Bump nextjs-t3 to next 15

[chargome]

Latest t3 runs on next 15 so this makes more sense imo.

Closes #19131 (added automatically)

[github-actions]

Codecov Results 📊

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Generated by Codecov Action

[github-actions]

node-overhead report 🧳

Note: This is a synthetic benchmark with a minimal express app and does not necessarily reflect the real-world performance impact in an application.

Scenario	Requests/s	% of Baseline	Prev. Requests/s	Change %
GET Baseline	8,957	-	11,574	-23%
GET With Sentry	1,702	19%	1,956	-13%
GET With Sentry (error only)	6,232	70%	7,679	-19%
POST Baseline	1,209	-	1,182	+2%
POST With Sentry	610	50%	598	+2%
POST With Sentry (error only)	1,057	87%	1,030	+3%
MYSQL Baseline	3,425	-	4,077	-16%
MYSQL With Sentry	452	13%	561	-19%
MYSQL With Sentry (error only)	2,711	79%	3,341	-19%

View base workflow run