[tests] Make record-test.sh work with .otf files

It hard-codes the file extension, but fonttools sunset will use .otf for
CFF fonts, so hard-code the output file from subset as well.

test/shaping/record-test.sh

diff --git a/test/shaping/record-test.sh b/test/shaping/record-test.sh
index 62a4795..963d180 100755
--- a/test/shaping/record-test.sh
+++ b/test/shaping/record-test.sh
@@ -65,16 +65,18 @@
 	--glyph-names \
 	--no-hinting \
 	--layout-features='*' \
-	"$dir/font.ttf" \
 	--gids="$glyph_ids" \
-	--text="$text"
+	--text="$text" \
+	--output-file="$dir/font.subset.ttf" \
+	"$dir/font.ttf"
 fonttools subset \
 	--glyph-names \
 	--no-hinting \
 	--layout-features='*' \
-	"$dir/font.ttf" \
 	--gids="$glyph_ids" \
-	--text="$text"
+	--text="$text" \
+	--output-file="$dir/font.subset.ttf" \
+	"$dir/font.ttf"
 if ! test -s "$dir/font.subset.ttf"; then
 	echo "Subsetter didn't produce nonempty subset font in $dir/font.subset.ttf" >&2
 	exit 2