unable to build with openssl 1.1.1 as hyper-tls is too old

I got this error while running cargo build

   Compiling openssl v0.9.24
   Compiling tokio-threadpool v0.1.14
   Compiling logging v0.1.0 (/home/e/Local/exodus/logging)
   Compiling phf_generator v0.7.24
   Compiling mio-uds v0.6.7
error: failed to run custom build command for `openssl v0.9.24`
process didn't exit successfully: `/home/e/Local/exodus/target/debug/build/openssl-25e0f4547135f68b/build-script-build` (exit code: 101)
thread 'main' panicked at 'Unable to detect OpenSSL version', /home/e/.cargo/registry/src/github.com-1ecc6299db9ec823/openssl-0.9.24/build.rs:16:14
note: Run with `RUST_BACKTRACE=1` environment variable to display a backtrace.

My symptom is exactly the same as this issue. It seems that the the dependency hyper-tls is so old that it requires the old-fashioned openssl v0.9.24.

ExodusVPN / exodus

unable to build with openssl 1.1.1 as hyper-tls is too old #23