rustic fix(rustic-babel): disable toolchain when invalid/unneeded

When the user installs Rust tools using a method other than rustup, e.g. using an operating system's package manager, cargo generally has no support for toolchain specification. In such case, the user can then nil, or "", so that the rescpective functions in `rustic-babel' will remove the toolchain from params, that is only toolchain has a valid value it uses toolchain.

See also: https://github.com/brotzeit/rustic/pull/279#issuecomment-1336164427, https://github.com/brotzeit/rustic/issues/498

Mar 26 '23 16:03 yuuyins

i did this fix a while ago and works for me, unsure if it's fit. can't remember why i didn't PR

Mar 26 '23 16:03 yuuyins

working for me with (setq rustic-babel-default-toolchain nil)

Apr 22 '23 23:04 yuuyins

forgot about the test i'll have to look into it

Apr 22 '23 23:04 yuuyins

@psibi yes, please you can merge it. ah, it seems the existing tests are failing

Apr 24 '23 11:04 yuuyins

@yuuyins Sorry, it seems there is some test failures. Can you look into it ?

Apr 24 '23 12:04 psibi

@psibi mind approving the workflow for us to determine if the PR still fails or not?

May 26 '23 20:05 StrictlyMonad