evtest: update sha256 hash

Commit 6df37c9aab bumped the version of
evtest but failed to update the hash.  As a result, hosts which
already have evtest-1.33 source present will build the old version but
label it as evtest-1.34.  Hosts which lack the older source code will
fail their builds.  This commit corrects the issue.

We should think about a way to get Hydra to catch issues like this.
Maybe require that if two FODs have different hashes then they must
have different `${pname}-${version}`s?  Only for FODs, of course.

pkgs/applications/misc/evtest/default.nix

@@ -10,7 +10,7 @@ stdenv.mkDerivation rec {
   src = fetchgit {
     url = "git://anongit.freedesktop.org/${pname}";
     rev = "refs/tags/${pname}-${version}";
-    sha256 = "168gdhzj11f4nk94a6z696sm8v1njzwww69bn6wr97l17897913g";
+    sha256 = "sha256-0UGcoGkNF/19aSTWNEFAmZP7seL/yObXsOLlZLiyG2Q=";
   };
 
   meta = with lib; {