Add Clippy exceptions

This is primarily to pass CI.

The exception added on `find` is because it is a candidate for
replacement with a non-recursive version.

dotenv/src/find.rs

@@ -34,6 +34,7 @@ impl<'a> Finder<'a> {
 }
 
 /// Searches for `filename` in `directory` and parent directories until found or root is reached.
+#[allow(clippy::option_if_let_else)]
 pub fn find(directory: &Path, filename: &Path) -> Result<PathBuf> {
     let candidate = directory.join(filename);
 

dotenv/src/lib.rs

@@ -1,5 +1,5 @@
 #![warn(clippy::all, clippy::pedantic, clippy::nursery, clippy::cargo)]
-#![allow(clippy::missing_errors_doc)]
+#![allow(clippy::missing_errors_doc, clippy::too_many_lines)]
 
 //! [`dotenv`]: https://crates.io/crates/dotenv
 //! A well-maintained fork of the [`dotenv`] crate