Rework test to avoid diverging eclipse output

If a record is part of a class some eclipse/ecj versions add the
implicit static modifier to the output and some doesn't. If the record
is nested in another record this doesn't happen.

test/transform/resource/after-delombok/WithOnNestedRecord.java

@@ -1,5 +1,5 @@
 // version 14:
-public class WithOnNestedRecord<T> {
+public record WithOnNestedRecord<T>() {
 
 	public record Nested(String a, String b) {
 		/**