[DOCS] Drafted 6.2.2 release notes
[DOCS] Drafted 6.2.2 release notes

Original commit: elastic/x-pack-elasticsearch@89eff13bd74f3625c3e99373f6cd0ce0ea44047f

vroyer/elassandra,vroyer/elassandra,vroyer/elassandra,strapdata/elassandra,strapdata/elassandra,strapdata/elassandra,strapdata/elassandra,strapdata/elassandra