tests: streamline module names to unit_tests

This better aligns with the rest of the code and makes it clearer
that these tests can run "as is" in a normal hosted environments
without the special test environment.

Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com

rate_limiter/src/group.rs

@@ -297,7 +297,7 @@ impl Drop for RateLimiterGroup {
 }
 
 #[cfg(test)]
-pub(crate) mod tests {
+pub(crate) mod unit_tests {
     use std::os::fd::AsRawFd;
     use std::thread;
     use std::time::Duration;

rate_limiter/src/lib.rs

@@ -522,7 +522,7 @@ impl Default for RateLimiter {
 }
 
 #[cfg(test)]
-pub(crate) mod tests {
+pub(crate) mod unit_tests {
     use std::{fmt, thread};
 
     use super::*;