SDL_ttf: update vendored harfbuzz (ca898)

From ca898d188568ae4b6acd01c5a40f864d7a77c9ab Mon Sep 17 00:00:00 2001
From: Ozkan Sezer <[EMAIL REDACTED]>
Date: Fri, 31 May 2024 20:01:02 +0300
Subject: [PATCH] update vendored harfbuzz

---
 external/harfbuzz | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/external/harfbuzz b/external/harfbuzz
index 516b7ed0..e18e6640 160000
--- a/external/harfbuzz
+++ b/external/harfbuzz
@@ -1 +1 @@
-Subproject commit 516b7ed0b022ab0ffeb0cee87d31d9c40d3a54df
+Subproject commit e18e66409d0136cc8f8b05aac791f84314520676