[GR-39313] Avoid NPEs in includeAnnotation when annotationValue is null

[zakkak]

Fixes issue introduced in CI runs by #4614

null AnnotationValues may be generated in

graal/substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/annotation/AnnotationValue.java

Lines 69 to 71 in d5fae29

	if (skipMembers) {
	return null;
	}

[loicottet]

Thanks for the catch!