Fix typo in test16096.sh: ${EXT} -> ${EXE}

[ThomasMader]

cc @wilzbach

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[wilzbach]

Hmm I wonder why it passed on the testsuite as the script that sources this does among other a set -u

[ThomasMader]

Hmm I wonder why it passed on the testsuite as the script that sources this does among other a set -u

Strange indeed. I got a EXT: unbound variable on MacOS with Nix but on NixOS (Linux) it was not a problem.