libextractor: 1.6 -> 1.7 (#43756)

Semi-automatic update generated by https://github.com/ryantm/nixpkgs-update tools. This update was made based on information from https://repology.org/metapackage/libextractor/versions.

pkgs/development/libraries/libextractor/default.nix

···
 assert videoSupport -> ffmpeg != null && libmpeg2 != null;
 
 stdenv.mkDerivation rec {
-  name = "libextractor-1.6";
+  name = "libextractor-1.7";
 
   src = fetchurl {
     url = "mirror://gnu/libextractor/${name}.tar.gz";
-    sha256 = "17gnpgspdhfgcr27j8sn9105vb4lw22yqdrhic62l79q5v5avm16";
+    sha256 = "13wf6vj7mkv6gw8h183cnk7m24ir0gyf198pyb2148ng4klgv9p0";
   };
 
   preConfigure =