Add code signing instructions for libs

Author: def-

ddnet-lib-update.sh

@@ -531,3 +531,6 @@ cp .libs/libpng16.16.dylib ..
 # create fat binaries for mac
 mkdir libfat; for i in lib64/*.dylib; do lipo -create $i libarm64/${i:t} -output libfat/${i:t}; done
 mkdir libfat; for i in lib64/*.a; do lipo -create $i libarm64/${i:t} -output libfat/${i:t}; done
+
+# sign all arm64 and fat dylibs using codesign on macOS (until https://github.com/thefloweringash/sigtool/issues/8 is fixed, then we can automate it on Linux)
+for i in **/libarm64/*.dylib **/libfat/*.dylib mac/libarm64/SDL2.framework mac/libfat/SDL2.framework; do codesign -s - $i; done