Remove `$(TOP)/ANNOUNCE` file
Remove `$(TOP)/ANNOUNCE` file

Remove `$(TOP)/ANNOUNCE` because maintaining this file is expensive
for each release.

Currently, release announcements of ghc are made on ghc blogs and wikis.

[skip ci]

sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc