MSRV should be atleast 1.70

This is due to parse-display-derive using regex with https://doc.rust-lang.org/std/cell/struct.OnceCell.html which has became stable in 1.70.

error[E0658]: use of unstable library feature 'once_cell'
   --> /home/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/parse-display-derive-0.9.0/src/regex_utils.rs:98:20
    |
98  |         static RE: ::std::sync::OnceLock<regex::Regex> = ::std::sync::OnceLock::new();
    |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
   ::: /home/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/parse-display-derive-0.9.0/src/lib.rs:348:28
    |
348 |         let regex_number = regex!("^[0-9]+$");
    |                            ------------------ in this macro invocation
    |
    = note: see issue #74465 <https://github.com/rust-lang/rust/issues/74465> for more information
    = note: this error originates in the macro `regex` (in Nightly builds, run with -Z macro-backtrace for more info)

PS: I'd propose to also run CI with MSRV version and set rust-version in Cargo.toml's package

frozenlib / parse-display

MSRV should be atleast 1.70 #42