dev-lang/swift: fix swift-6.3 SLOT

swift-6.3 was accidentally introduced with a SLOT of "6/2" when it
should be "6/3"

Signed-off-by: Itai Ferber <itai@itaiferber.net>

dev-lang/swift/swift-6.3-r1.ebuild

@@ -67,7 +67,7 @@ PATCHES=(
 
 S="${WORKDIR}"
 LICENSE="Apache-2.0"
-SLOT="6/2"
+SLOT="6/3"
 KEYWORDS="~amd64"
 REQUIRED_USE="${PYTHON_REQUIRED_USE}"