Use our own dependencies for SFML in the CSFML NuGet

tools/nuget/build.linux.sh

@@ -94,6 +94,7 @@ cmake -E env LDFLAGS="-z origin" \
     "-DCMAKE_LIBRARY_OUTPUT_DIRECTORY=$SFMLLibDir" \
     '-DCMAKE_BUILD_WITH_INSTALL_RPATH=ON' \
     '-DCMAKE_INSTALL_RPATH=$ORIGIN' \
+    '-DSFML_USE_SYSTEM_DEPS=OFF' \
     '-DSFML_BUILD_NETWORK=OFF' \
     "$SFMLDir"