firefox-bin: libpulseaudio.dev is needed otherwise firefox doesn't start

pkgs/applications/networking/browsers/firefox-bin/default.nix

···
       nss
       pango
       libheimdal
-      libpulseaudio
+      libpulseaudio.dev
       systemd
     ] + ":" + stdenv.lib.makeSearchPathOutput "lib" "lib64" [
       stdenv.cc.cc