libbson: 1.9.3 -> 1.9.4

Semi-automatic update generated by https://github.com/ryantm/nixpkgs-update tools.

This update was made based on information from https://repology.org/metapackage/libbson/versions.

These checks were done:

- built on NixOS
- Warning: no binary found that responded to help or version flags. (This warning appears even if the package isn't expected to have binaries.)
- found 1.9.4 with grep in /nix/store/120cz3gc3s0hasql1p3zc3sgjzvn4753-libbson-1.9.4
- directory tree listing: https://gist.github.com/da41b1208cf5cb999e6de11ad1fb2fc6

pkgs/development/libraries/libbson/default.nix

@@ -2,13 +2,13 @@
 
 stdenv.mkDerivation rec {
   name = "libbson-${version}";
-  version = "1.9.3";
+  version = "1.9.4";
 
   src = fetchFromGitHub {
     owner = "mongodb";
     repo = "libbson";
     rev = version;
-    sha256 = "0dbpmvd2p9bdqdyiijmsc1hd9d6l36migk79smw7fpfvh0y6ldsk";
+    sha256 = "01lyikbpqky1ib8g4vhwpb5rjwyzm6g1z24z8m73lk4vcdl65190";
   };
 
   nativeBuildInputs = [ cmake ];