GitHub CI: Disable Toooba test for macos-13

[quark17]

The elf_to_hex program in Toooba segfaults on macos-13, causing the job to fail. Until this is resolved, this PR disables the Toooba test for macos-13.

An alternative would be to keep a pre-built hex file somewhere, but I'm not sure what's the best way to do that.

I don't have macos-13 to debug the segfault on. I tried running gdb in the VM, but that seems to hang -- and also hangs when run on my macos-11 system. I then tried valgrind, but I couldn't get it installed -- the configure step said that the kernel version is unsupported (even though it says it supports macOS 13).

[pbing]

I only have macOS 14.3.1 but the crash remains.

% brew list libelf
/opt/homebrew/Cellar/libelf/0.8.13_1/include/libelf/ (5 files)
/opt/homebrew/Cellar/libelf/0.8.13_1/lib/locale/de/LC_MESSAGES/libelf.cat
/opt/homebrew/Cellar/libelf/0.8.13_1/lib/pkgconfig/libelf.pc
/opt/homebrew/Cellar/libelf/0.8.13_1/lib/libelf.a

% DYLD_PRINT_SEARCHING=1 ./elf_to_hex
dyld[32765]: dyld cache '(null)' not loaded: syscall to map cache into shared region failed
dyld[32765]: find path "/usr/lib/libSystem.B.dylib"
dyld[32765]:   possible path(DYLD_FRAMEWORK/LIBRARY_PATH): "/libSystem.B.dylib"
dyld[32765]: no pseudo-dylibs to search
dyld[32765]:   possible path(original path on disk): "/usr/lib/libSystem.B.dylib"
dyld[32765]: no pseudo-dylibs to search
dyld[32765]:   possible path(cryptex prefix): "/System/Volumes/Preboot/Cryptexes/OS/usr/lib/libSystem.B.dylib"
dyld[32765]: no pseudo-dylibs to search
dyld[32765]:   possible path(original path): "/usr/lib/libSystem.B.dylib"
dyld[32765]: no pseudo-dylibs to search
dyld[32765]:   not found: "/usr/lib/libSystem.B.dylib"
dyld[32765]: Library not loaded: /usr/lib/libSystem.B.dylib
  Referenced from: <ACDF1525-3B48-3C9F-9191-E86168FE9DD1> /Users/bernd/Projects/github.com/pbing/AXI4-Lite/Piccolo/Tests/elf_to_hex/elf_to_hex
  Reason: tried: '/libSystem.B.dylib' (no such file), '/usr/lib/libSystem.B.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/usr/lib/libSystem.B.dylib' (no such file), '/usr/lib/libSystem.B.dylib' (no such file, no dyld cache)
zsh: abort      DYLD_PRINT_SEARCHING=1 ./elf_to_hex

It seems that libelf is compiled with incompatible libraries for the actual macOS versions.