Delete x-revision field from hackage-security-HTTP.cabal

The .cabal file contains at this point changes we do not want to
release in a revision.

Author: andreasabel

hackage-security-HTTP/hackage-security-HTTP.cabal

@@ -1,7 +1,7 @@
 cabal-version:       1.12
 name:                hackage-security-HTTP
 version:             0.1.1.1
-x-revision:          8
+
 synopsis:            Hackage security bindings against the HTTP library
 description:         The hackage security library provides a 'HttpLib'
                      abstraction to allow to bind against different HTTP