Release Notes from：release/ver-2.4.0.18 to：release/ver-2.4.0.20

FIX BUGS: TDengine fix: reverseCopy not support timestamp datatype (#12340) fix: group by with proj query can not work well (#12288) fix: apply function offset/forward step error when session + order by ts desc (#12271) fix: make least-squares buffer large enough to hold json result (#12205) fix: backport last expr fix from develop branch (#12140) fix: disallow order by tbname for temp table (#12021) fix: fixed a query coredump in Windows (#11945) fix: update copoyright info (#12308)

ENHANCEMENTS: TDengine refactor: V2.4 move TSZ to main repo (#12236)