[trivial] Remove an unused local variable

[kubo39]

No description provided.

[dlang-bot]

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Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub fetch digger
dub run digger -- build "master + dmd#9337"

[thewilsonator]

http://downloads.dlang.org/releases/2.x/2.079.1/dmd.2.079.1.linux.tar.xz | tar -C ../generated/host_dmd-2.079.1 -Jxf - || rm -rf ../generated/host_dmd-2.079.1
xz: (stdin): Compressed data is corrupt
tar: Unexpected EOF in archive
tar: Unexpected EOF in archive
tar: Error is not recoverable: exiting now
curl: (23) Failed writing body (561 != 8592)

Urgh.