fix(deps): update nextjs monorepo to v15 #2050

Job	Run time
build-start-form-springboot	51s
build-element-template-generation	5m 10s
build-async-service-task	1m 38s
build-event-processing	1m 38s
build-large-multi-instance-example	1m 8s
build-parallel-operations	1m 8s
build-payment-example-process-application	5m 11s
build-react-tasklist	1m 27s
build-rollback-on-error-example	1m 28s
build-synchronous-response-springboot	47s
build-timer-testing	3m 6s
build-twitter-review-java-springboot	1m 33s
build-zeebe-client-plain-java	29s
	25m 34s

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