Remove dependency on libssl

[SteveL-MSFT]

PR Summary

Explicitly use rustls-tls and set default-features to false for reqwest so that it doesn't use libssl

PS> ldd ./bin/debug/dsc
        linux-vdso.so.1 (0x00007fff761ea000)
        libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007efd595ee000)
        libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007efd59507000)
        libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007efd592de000)
        /lib64/ld-linux-x86-64.so.2 (0x00007efd5b29d000)

PR Context

Fix #442