fix: correctly set target java version #6215

Job	Run time
check_format_and_unit_tests	1m 50s
build / Special integration tests (17)	2m 7s
build / Special integration tests (25)	2m 17s
build / Special integration tests (21)	2m 17s
build / httpclient-tests (jetty) / Integration tests (25, 1.32.0, jetty)	11m 44s
build / httpclient-tests (jdk) / Integration tests (25, 1.32.0, jdk)	11m 44s
build / integration_tests (17, 1.31.8) / Integration tests (17, 1.31.8, vertx)	11m 42s
build / integration_tests (25, 1.32.4) / Integration tests (25, 1.32.4, vertx)	11m 44s
build / integration_tests (21, 1.31.8) / Integration tests (21, 1.31.8, vertx)	11m 42s
build / integration_tests (17, 1.33.1) / Integration tests (17, 1.33.1, vertx)	11m 43s
build / integration_tests (25, 1.30.12) / Integration tests (25, 1.30.12, vertx)	11m 42s
build / integration_tests (25, 1.33.1) / Integration tests (25, 1.33.1, vertx)	11m 43s
build / integration_tests (17, 1.30.12) / Integration tests (17, 1.30.12, vertx)	11m 43s
build / integration_tests (21, 1.32.4) / Integration tests (21, 1.32.4, vertx)	11m 43s
build / integration_tests (21, 1.30.12) / Integration tests (21, 1.30.12, vertx)	11m 43s
build / integration_tests (17, 1.32.4) / Integration tests (17, 1.32.4, vertx)	11m 42s
build / httpclient-tests (vertx) / Integration tests (25, 1.32.0, vertx)	11m 42s
build / integration_tests (21, 1.33.1) / Integration tests (21, 1.33.1, vertx)	11m 42s
build / integration_tests (25, 1.31.8) / Integration tests (25, 1.31.8, vertx)	11m 45s
	3h 4m 15s

Provide feedback