Ignore missing_safety_doc clippy lint

    warning: unsafe function's docs miss `# Safety` section
        --> src/lib.rs:1240:5
         |
    1240 |     pub unsafe fn from_str_unchecked(repr: &str) -> Self {
         |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
         |
         = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#missing_safety_doc
         = note: `-W clippy::missing-safety-doc` implied by `-W clippy::all`
         = help: to override `-W clippy::all` add `#[allow(clippy::missing_safety_doc)]`

src/lib.rs

@@ -98,6 +98,7 @@
     clippy::let_underscore_untyped,
     clippy::manual_assert,
     clippy::manual_range_contains,
+    clippy::missing_safety_doc,
     clippy::must_use_candidate,
     clippy::needless_doctest_main,
     clippy::new_without_default,