Fix #14884 fuzzing timeout (hang) in TemplateSimplifier::expandTempla… #20240

Job	Run time
build_cmake (ubuntu:25.10, true, true)	5m 45s
build_cmake (alpine:3.23, false, false)	4m 38s
build_make (ubuntu:24.04)	4m 34s
build_cmake (ubuntu:24.04, true, true)	5m 40s
build_make (ubuntu:25.10)	5m 10s
build_make (alpine:3.23)	5m 19s
	31m 6s

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