chore(directory): fix typo (#3364)

seperators -> separators

src/modules/directory.rs

@@ -327,7 +327,7 @@ fn to_fish_style(pwd_dir_length: usize, dir_string: String, truncated_dir_string
         .join("/")
 }
 
-/// Convert the path seperators in `path` to the OS specific path seperators.
+/// Convert the path separators in `path` to the OS specific path separators.
 fn convert_path_sep(path: &str) -> String {
     return PathBuf::from_slash(path).to_string_lossy().into_owned();
 }