gnu: texlive-bin: Patch to fix non-deterministic test.

* gnu/packages/patches/texlive-bin-luaoutputdir-test.patch: New file.
* gnu/local.mk (dist_patch_DATA): Register it.
* gnu/packages/tex.scm (texlive-bin): Apply it.

Fixes: #1628
Change-Id: I3d99a033c123c35f562879ea1cccca87a7267574

gnu/local.mk

@@ -2366,6 +2366,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/texi2html-document-encoding.patch	\
   %D%/packages/patches/texi2html-i18n.patch			\
   %D%/packages/patches/texmacs-wayland-hidpi.patch	\
+  %D%/packages/patches/texlive-bin-luaoutputdir-test.patch      \
   %D%/packages/patches/thefuck-test-environ.patch		\
   %D%/packages/patches/thefuck-remove-broken-tests.patch	\
   %D%/packages/patches/tidy-CVE-2015-5522+5523.patch		\

gnu/packages/patches/texlive-bin-luaoutputdir-test.patch

@@ -0,0 +1,10 @@
+Retrieved from: <https://tug.org/pipermail/tex-live/2025-September/051785.html>
+
+--- a/texk/web2c/luatexdir/luaoutputdir.test	(revision 76261)
++++ b/texk/web2c/luatexdir/luaoutputdir.test	(working copy)
+@@ -14,4 +14,5 @@
+ outdir=tests/outdirlua
+ outfile=outfileLUA.tex
+ rm -rf $outdir  # don't let previous runs interfere
++test -d tests || mkdir -p tests # ensure subdir exists
+ mkdir $outdir || exit 1

gnu/packages/tex.scm

@@ -826,7 +826,8 @@ and should be preferred to it whenever a package would otherwise depend on
               (for-each
                delete-file-recursively
                (scandir "." (lambda (f)
-                              (not (member f '("." ".." "texmf.cnf")))))))))))
+                              (not (member f '("." ".." "texmf.cnf")))))))))
+       (patches (search-patches "texlive-bin-luaoutputdir-test.patch"))))
     (build-system gnu-build-system)
     (arguments
      (list