Add alfred-margaret and hackage-revdeps

build-constraints.yaml

@@ -3665,6 +3665,8 @@ packages:
         - snap-server
         - cabal-add
         - cabal-install-parsers
+        - alfred-margaret
+        - hackage-revdeps
 
     "Ashley Yakeley <ashley@semantic.org> @AshleyYakeley":
         - countable
@@ -8151,6 +8153,9 @@ package-flags:
     cabal-add:
       cabal-syntax: true
 
+    hackage-revdeps:
+      cabal-syntax: true
+
     aws-sns-verify:
       development: true