refactor: make logout works on safari (#442)

src/auth.rs

@@ -429,7 +429,8 @@ fn is_readonly_method(method: &Method) -> bool {
         || method == Method::OPTIONS
         || method == Method::HEAD
         || method.as_str() == "PROPFIND"
-        || method.as_str() == "AUTH"
+        || method.as_str() == "CHECKAUTH"
+        || method.as_str() == "LOGOUT"
 }
 
 fn strip_prefix<'a>(search: &'a [u8], prefix: &[u8]) -> Option<&'a [u8]> {