SDL: Fixed "${folder^}Activity: bad substitution" with bash 3.2 on macOS

From c36f773eb47693ad360dd3c97c347e9ab07cfa4c Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Tue, 5 Mar 2024 13:10:27 -0800
Subject: [PATCH] Fixed "${folder^}Activity: bad substitution" with bash 3.2 on
 macOS

---
 build-scripts/androidbuild.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/build-scripts/androidbuild.sh b/build-scripts/androidbuild.sh
index ec71cbcad0b6..1a107e27dee2 100755
--- a/build-scripts/androidbuild.sh
+++ b/build-scripts/androidbuild.sh
@@ -81,7 +81,7 @@ do
 done
 
 # Uppercase the first char in the activity class name because it's Java
-ACTIVITY="${folder^}Activity"
+ACTIVITY="$(echo $folder | awk '{$1=toupper(substr($1,0,1))substr($1,2)}1')Activity"
 sed -i -e "s|\"SDLActivity\"|\"$ACTIVITY\"|g" $BUILDPATH/app/src/main/AndroidManifest.xml
 
 # Fill in a default Activity