ECJ has been enhanced to warn about unused lambda parameters
(https://github.com/eclipse-jdt/eclipse.jdt.core/pull/3053 ) but
templates are done for lowest Java version supported without an easy way
to generate per JVM versioned code thus there is no easy way to change
them.
Filter these warnings until Java 22 is the min required version for
templates.
Fixes I-build tests
https://download.eclipse.org/eclipse/downloads/drops4/I20241015-1820/testresults/html/org.eclipse.pde.ui.templates.tests_ep434I-unit-cen64-gtk3-java23_linux.gtk.x86_64_23.html