idea: add `libsecret` to the library path

This solves the `Cannot access native keychain` warning from
IntelliJ-based IDEs. Previously IDEA was unable to find `libsecret` as
it was not part of its library path.

Please keep in mind that the keyring daemon that can be enabled on
NixOS with `services.gnome3.gnome-keyring.enable = true` must be
running.

pkgs/applications/editors/jetbrains/common.nix

···
 { stdenv, fetchurl, makeDesktopItem, makeWrapper, patchelf, p7zip
-, coreutils, gnugrep, which, git, python, unzip }:
+, coreutils, gnugrep, which, git, python, unzip, libsecret
+}:
 
 { name, product, version, src, wmClass, jdk, meta } @ attrs:
 
···
       --prefix PATH : "$out/libexec/${name}:${stdenv.lib.makeBinPath [ jdk coreutils gnugrep which git ]}" \
       --prefix LD_LIBRARY_PATH : "${stdenv.lib.makeLibraryPath [
         # Some internals want libstdc++.so.6
-        stdenv.cc.cc.lib
+        stdenv.cc.cc.lib libsecret
       ]}" \
       --set JDK_HOME "$jdk" \
       --set ${hiName}_JDK "$jdk" \