Ports: Fix broken syntax in Milkytracker package script

Ports/milkytracker/package.sh

@@ -9,7 +9,7 @@ files=(
 configopts=("-DCMAKE_TOOLCHAIN_FILE=${SERENITY_BUILD_DIR}/CMakeToolchain.txt")
 depends=("SDL2" "zlib")
 launcher_name="MilkyTracker"
-launcher_category=&Media
+launcher_category='&Media'
 launcher_command=/usr/local/bin/milkytracker
 
 configure() {