AppImage the long way (#45)

fixed sdl and opengl i think

Reviewed-on: #45
Co-authored-by: swurl <swurl@swurl.xyz>
Co-committed-by: swurl <swurl@swurl.xyz>

.ci/linux.sh

@@ -50,8 +50,8 @@ cmake .. -G Ninja \
     -DYUZU_USE_BUNDLED_QT=OFF \
     -DUSE_SYSTEM_QT=ON \
     -DYUZU_USE_BUNDLED_FFMPEG=OFF \
-    -DYUZU_USE_BUNDLED_SDL2=ON \
-    -DYUZU_USE_EXTERNAL_SDL2=OFF \
+    -DYUZU_USE_BUNDLED_SDL2=OFF \
+    -DYUZU_USE_EXTERNAL_SDL2=ON \
     -DYUZU_TESTS=OFF \
     -DYUZU_USE_LLVM_DEMANGLE=OFF \
     -DYUZU_USE_QT_MULTIMEDIA=OFF \
@@ -61,6 +61,7 @@ cmake .. -G Ninja \
     -DBUNDLE_SPEEX=ON \
     -DYUZU_USE_FASTER_LD=OFF \
     -DYUZU_ENABLE_LTO=ON \
+    -DCMAKE_LINKER=/usr/bin/mold \
 	"${EXTRA_CMAKE_FLAGS[@]}"
 
 ninja -j${NPROC}