use latest mbedtls v3.6.3

Change-Id: I92fc728e301c256158d5a39087f80c40b857f1fa
Signed-off-by: Lauren Wehrmeister <lauren.wehrmeister@arm.com>
diff --git a/tf-a-windows-builder.yaml b/tf-a-windows-builder.yaml
index a873713..3aab760 100644
--- a/tf-a-windows-builder.yaml
+++ b/tf-a-windows-builder.yaml
@@ -44,7 +44,7 @@
           default: +refs/heads/master:refs/remotes/origin/master
       - string:
           name: MBEDTLS_URL
-          default: https://github.com/Mbed-TLS/mbedtls/archive/mbedtls-3.6.2.tar.gz
+          default: https://github.com/Mbed-TLS/mbedtls/archive/mbedtls-3.6.3.tar.gz
       - string:
           name: PARAMS
           description: Debug parameters for make