chore: use -rdynamic instead of -export-dynamic

Summary

• chore: use -rdynamic instead of -export-dynamic

It has been observed that on Fedora -export-dynamic triggers some reincarnation of this bug: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47390

TLDR: it treated leading -e as entrypoint argument so resulting binary was completely broken, i e there was no main in it and entrypoint was set to unrelated deregister_tm_clones. Big thanks to @gmoshkin for finding the solution and to @funbringer for assistance with debugging

Ensure that

• New code is covered by tests
• API is documented
• Changelog is up to date
• (if Lua API changed) Lua API version is bumped in luamod.rs
• (if necessary) A follow-up doc issue is created in picodata/docs and linked here