It installed about 70% of the dependencies it needed to get ffmpegs going, but it got stuck at installing 'doxygen'.

This is the error I got:

```
==> Installing dependencies for ffmpeg: doxygen, little-cms2, openjpeg, opus, rust, libgit2, cargo-c, rav1e, flac, libsndfile, libsamplerate, rubberband, sdl2, swig, llvm, snappy, speex, srt, leptonica, libb2, lz4, libarchive, tesseract, theora, x264, x265, xvid, docbook, boost, source-highlight, asciidoc, docbook-xsl, libyaml, ruby, asciidoctor, gnu-getopt, xmlto, libsodium, zeromq and zimg
==> Installing ffmpeg dependency: doxygen
==> cmake ..
==> make
Last 15 lines from /Users/macbook/Library/Logs/Homebrew/doxygen/02.make:
In file included from /tmp/doxygen-20220723-61533-5m5mdv/doxygen-1.9.4/src/outputlist.h:25:
/tmp/doxygen-20220723-61533-5m5mdv/doxygen-1.9.4/src/searchindex.h:29:10: fatal error: 'variant' file not found
#include <variant>
         ^~~~~~~~~
1 error generated.
make[2]: *** [src/CMakeFiles/doxymain.dir/__/generated_src/code.cpp.o] Error 1
make[1]: *** [src/CMakeFiles/doxymain.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....
[ 46%] Linking CXX static library ../lib/libvhdlparser.a
cd /tmp/doxygen-20220723-61533-5m5mdv/doxygen-1.9.4/build/vhdlparser && /usr/local/Cellar/cmake/3.23.2/bin/cmake -P CMakeFiles/vhdlparser.dir/cmake_clean_target.cmake
cd /tmp/doxygen-20220723-61533-5m5mdv/doxygen-1.9.4/build/vhdlparser && /usr/local/Cellar/cmake/3.23.2/bin/cmake -E cmake_link_script CMakeFiles/vhdlparser.dir/link.txt --verbose=1
/usr/bin/ar qc ../lib/libvhdlparser.a CMakeFiles/vhdlparser.dir/CharStream.cc.o CMakeFiles/vhdlparser.dir/ParseException.cc.o CMakeFiles/vhdlparser.dir/Token.cc.o CMakeFiles/vhdlparser.dir/TokenMgrError.cc.o CMakeFiles/vhdlparser.dir/__/generated_src/VhdlParser_adj.cc.o CMakeFiles/vhdlparser.dir/VhdlParserTokenManager.cc.o
/usr/bin/ranlib ../lib/libvhdlparser.a
[ 46%] Built target vhdlparser
make: *** [all] Error 2

Do not report this issue to Homebrew/brew or Homebrew/core!

Error: You are using macOS 10.12.
We (and Apple) do not provide support for this old version.
You will encounter build failures with some formulae.
Please create pull requests instead of asking for help on Homebrew's GitHub,
Twitter or any other official channels. You are responsible for resolving
any issues you experience while you are running this
old version.

```

Can someone please help me am not sure what it is, that I am supposed to do.