treewide: http -> https sources (#42676)

* treewide: http -> https sources

This updates the source urls of all top-level packages from http to
https where possible.

* buildtorrent: fix url and tab -> spaces

pkgs/tools/networking/dhcp/default.nix

@@ -7,7 +7,7 @@ stdenv.mkDerivation rec {
   version = "4.4.1";
 
   src = fetchurl {
-    url = "http://ftp.isc.org/isc/dhcp/${version}/${name}.tar.gz";
+    url = "https://ftp.isc.org/isc/dhcp/${version}/${name}.tar.gz";
     sha256 = "025nfqx4zwdgv4b3rkw26ihcj312vir08jk6yi57ndmb4a4m08ia";
   };