[DOC] PG18 Full support (PMM-14517)#4845

catalinaadam wants to merge 6 commits intodoc_3.6.0percona/pmm:doc_3.6.0from

DOC_PG18_FULL_SUPPORTpercona/pmm:DOC_PG18_FULL_SUPPORTCopy head branch name to clipboard