fix(Popper): add null & connected checks for document [6.4.x patch]#12286

kmcfaul wants to merge 2 commits intopatternfly:6.4.xpatternfly/patternfly-react:6.4.xfrom

kmcfaul:6.4-popper-documentcheckkmcfaul/patternfly-react:6.4-popper-documentcheckCopy head branch name to clipboard