- Use latest stable for rustfmt and clippy. - Update Rust in rust-toolchain and coredeps Docker container to 1.54.0 and test against it. - Test against 1.48.0 to ensure libdeltachat can be compiled with Debian bullseye "rustc" and "cargo".
Old miniperl segfaults on the latest manylinux image
Python 3.5 is removed from the latest manylinux2014 images