Compile error when building cli

[m3dwards]

When running cargo install --path sim-cli/

I got:

error[E0308]: mismatched types
  --> sim-lib/src/cln.rs:78:17
   |
78 |                 alias,
   |                 ^^^^^ expected `String`, found `Option<String>`
   |
   = note: expected struct `std::string::String`
                found enum `std::option::Option<std::string::String>`