Use execinfo.h instead of libbacktrace

[cole-miller]

@just-now suggested this

https://man7.org/linux/man-pages/man3/backtrace.3.html

[cole-miller]

what will be involved in this:

• get rid of the --enable-backtrace switch in configure.ac, don't try to link libbacktrace
• in configure.ac, check for the execinfo.h header and use that to set DQLITE_ASSERT_WITH_BACKTRACE
• get rid of src/raft/assert.h and use src/assert.h everywhere
• rewrite the code in src/assert.h to use the execinfo.h functions instead of the libbacktrace API
• test to make sure a backtrace is generated as expected when using glibc + gcc and glibc + clang. Bonus: see what happens with musl
• remove --enable-backtrace and libbacktrace installation from our CI

[cole-miller]

I can't assign the issue to him but @letFunny is working on this

[cole-miller]

Closing because the execinfo.h API doesn't read DWARF info, hence you can't get a helpful backtrace unless you postprocess it with addr2line, which makes this feature less convenient for quick debugging -- and quick debugging is really what it's good for.