remote: actually use build-remote flag, disable by default, enable via cabal.project

Author: sorki

cabal.project

@@ -1 +1,7 @@
-packages: ./hnix-store-core/*.cabal ./hnix-store-remote/*.cabal
+packages:
+  ./hnix-store-core/hnix-store-core.cabal
+  ./hnix-store-remote/hnix-store-remote.cabal
+
+package hnix-store-remote
+  flags: +build-readme
+

hnix-store-remote/hnix-store-remote.cabal

@@ -60,7 +60,7 @@ flag io-testsuite
 
 flag build-readme
   default:
-    True
+    False
   description:
     Build README.lhs example
 
@@ -97,6 +97,8 @@ library
   ghc-options:         -Wall
 
 executable remote-readme
+  if !flag(build-readme)
+    buildable: False
   build-depends:
       base >=4.12 && <5
     , hnix-store-remote