Update to Fedora 39, update all toolchains

- Base image: Fedora 39
- SCons: 4.5.2
- Linux: GCC 10.2.0 built against glibc 2.19, binutils 2.35.1
- Windows: MinGW 11.0.0, GCC 13.2.1, binutils 2.40
- Web: Emscripten 3.1.39
- Android: Android NDK 23.2.8568313, build-tools 33.0.2, platform android-33, CMake 3.22.1, JDK 17
  CMake 3.22.1, JDK 17
- macOS: Xcode 15.0 with Apple Clang (LLVM 16.0.0), MacOSX SDK 14.0
- iOS: Xcode 15.0 with Apple Clang (LLVM 16.0.0), iPhoneOS SDK 17.0

Switches macOS/iOS builds to use Apple Clang, to maximize compatibility with
upstream Xcode.

Also add gettext which is needed by Godot build scripts to compile PO files
to MO.

Dockerfile.web

@@ -1,7 +1,7 @@
 ARG img_version
 FROM godot-fedora:${img_version}
 
-ENV EMSCRIPTEN_VERSION=3.1.18
+ENV EMSCRIPTEN_VERSION=3.1.39
 
 RUN git clone --branch ${EMSCRIPTEN_VERSION} --progress https://github.com/emscripten-core/emsdk && \
     emsdk/emsdk install ${EMSCRIPTEN_VERSION} && \