Ignore uninhabited_references clippy lint

    warning: dereferencing a reference to an uninhabited type is undefined behavior
      --> src/diff.rs:79:19
       |
    79 |             match *self {}
       |                   ^^^^^
       |
       = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#uninhabited_references
       = note: `-W clippy::uninhabited-references` implied by `-W clippy::all`
       = help: to override `-W clippy::all` add `#[allow(clippy::uninhabited_references)]`

src/lib.rs

@@ -230,6 +230,7 @@
     clippy::test_attr_in_doctest,
     clippy::too_many_lines,
     clippy::trivially_copy_pass_by_ref,
+    clippy::uninhabited_references,
     clippy::unused_self,
     clippy::while_let_on_iterator,
 )]