astroid: Remove mark as broken (#392429)

pkgs/applications/networking/mailreaders/astroid/default.nix

@@ -46,6 +46,7 @@ stdenv.mkDerivation rec {
       hash = "sha256-hZHOg1wUR8Kpd6017fWzhMmG+/WQxSOCnsiyIvUcpbU=";
     })
     (fetchpatch {
+      # error: 'is_regular' was not declared in this scope
       name = "boost_is_regular.patch";
       url = "https://github.com/astroidmail/astroid/commit/abd84171dc6c4e639f3e86649ddc7ff211077244.patch";
       hash = "sha256-IY60AnWm18ZwrCFsOvBg76UginpMo7gXBf8GT87FqW4=";
@@ -101,7 +102,5 @@ stdenv.mkDerivation rec {
     ];
     license = licenses.gpl3Plus;
     platforms = platforms.linux;
-    # error: 'is_regular' was not declared in this scope
-    broken = true;
   };
 }