Null field value triggers update

[noe-charmet]

We are using a CompositeController to maintain some pods with the Recreate strategy.
What I found out is that when the webhook returns a field as null/undefined, Kubernetes would not create that field. However metacontroller takes it into account when calculating its diff. This causes an infinite recreate loop as the field does not exist on the resource, but it is returned by the webhook as existing with a null value.

[grzesuav]

@noe-charmet is it the same as in #295 (comment) ?

[noe-charmet]

Yes it looks very much like it. Sorry for the double issue

[grzesuav]

no problem, I need to add this to troubleshooting section of documentation