gdalMinimal: skip test_zarr_read_simple_sharding

This test asserts that a Zarr tile-presence cache (zarr.json.gmac) is
written when opening a sharded array with CACHE_TILE_PRESENCE=YES. That
cache is serialized via the netCDF driver, which is disabled in the
minimal build, so the file is never created and the test fails.

The sibling test_zarr_cache_tile_presence is already gated on netCDF
upstream; this one was missed.

Fixes #540609

Assisted-by: Claude Opus 4.8

pkgs/by-name/gd/gdal/package.nix

@@ -309,6 +309,11 @@ stdenv.mkDerivation (finalAttrs: {
   ]
   ++ lib.optionals (!usePoppler) [
     "test_pdf_jpx_compression"
+  ]
+  ++ lib.optionals (!useNetCDF) [
+    # writes the Zarr tile-presence cache (.gmac) via the netCDF driver, which
+    # is absent in the minimal build
+    "test_zarr_read_simple_sharding"
   ];
   postCheck = ''
     popd # autotest