ci: we need sdl3-head, until SDL 3.4.0 ships.

Author: icculus

.github/workflows/main.yml

@@ -17,7 +17,7 @@ jobs:
       id: sdl
       uses: libsdl-org/setup-sdl@main
       with:
-        version: sdl3-latest
+        version: sdl3-head
     - name: Get MojoAL sources
       uses: actions/checkout@v3
     - name: Configure CMake