aspellWithDicts: fix data-dir path

In 52a23a9 the configuration `data-dir $out/share/aspell` was
introduced to make sure that `aspell --lang=<LANG> create
master ...` finds the LANG.dat file. However, the correct location
for language data files is $out/lib/aspell.  This confusion also
broke filter discovery as described in #476684.

This commit fixes the location of language data files.

Note: `aspell --lang=<LANG> create master ...` will fail if the
dictionary has not been installed in the environment via
`aspellWithDicts (dict: [ dict.<LANG> ])` which is expected.

Fixes #476684

pkgs/development/libraries/aspell/aspell-with-dicts.nix

@@ -30,7 +30,7 @@ buildEnv {
     pushd "${aspell}/bin"
     for prg in *; do
       if [ -f "$prg" ]; then
-        makeWrapper "${aspell}/bin/$prg" "$out/bin/$prg" --set ASPELL_CONF "dict-dir $out/lib/aspell; data-dir $out/share/aspell"
+        makeWrapper "${aspell}/bin/$prg" "$out/bin/$prg" --set ASPELL_CONF "dict-dir $out/lib/aspell; data-dir $out/lib/aspell"
       fi
     done
     popd