HBASE-26636 Update the ref guide upgrading section to mention that the master issue when upgrading to 2.3 (#3989)
HBASE-26636 Update the ref guide upgrading section to mention that the master issue when upgrading to 2.3 (#3989)

Signed-off-by: GeorryHuang <f49196cee701f909ce100abaf83336f3f51879b0@apache.org>
mahak/hbase,mahak/hbase,apurtell/hbase,Apache9/hbase,ndimiduk/hbase,mahak/hbase,apurtell/hbase,apurtell/hbase,mahak/hbase,Apache9/hbase,mahak/hbase,Apache9/hbase,mahak/hbase,Apache9/hbase,apurtell/hbase,ndimiduk/hbase,Apache9/hbase,apurtell/hbase,apurtell/hbase,mahak/hbase,ndimiduk/hbase,Apache9/hbase,Apache9/hbase,apurtell/hbase,ndimiduk/hbase,apurtell/hbase,ndimiduk/hbase,Apache9/hbase,Apache9/hbase,mahak/hbase,ndimiduk/hbase,Apache9/hbase,ndimiduk/hbase,mahak/hbase,ndimiduk/hbase,apurtell/hbase,ndimiduk/hbase,mahak/hbase,ndimiduk/hbase,apurtell/hbase