Bump io.undertow:undertow-core from 2.3.15.Final to 2.3.18.Final #1503

Job	Run time
Initial JDK 17 Weld Build + WildFly patch	3m 30s
Weld In-container Tests - JDK 17	6m 35s
CDI TCK - JDK 17	10m 37s
CDI TCK - JDK 21	10m 23s
CDI TCK SE - JDK 17	53s
Weld In-container Tests - JDK 21	7m 12s
CDI TCK SE - JDK 21	54s
Weld Tests w/o Container - JDK 17	3m 42s
Weld Examples build and test - JDK 17}	1m 7s
Weld Tests w/o Container - JDK 21	3m 23s
Relaxed mode testing - JDK 17	13m 54s
Weld SE-Servlet Cooperation	19s
	1h 2m 29s

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