fixes for tests to be run in release-mode

Signed-off-by: Jason Volk <jason@zemos.net>

src/core/utils/mod.rs

@@ -16,6 +16,7 @@ pub mod set;
 pub mod stream;
 pub mod string;
 pub mod sys;
+#[cfg(test)]
 mod tests;
 pub mod time;
 

src/core/utils/tests.rs

@@ -1,4 +1,3 @@
-#![cfg(test)]
 #![allow(clippy::disallowed_methods)]
 
 use crate::utils;