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

block/src/qcow/mod.rs

@@ -1815,7 +1815,7 @@ pub fn detect_image_type(file: &mut RawFile) -> Result<ImageType> {
 }
 
 #[cfg(test)]
-mod tests {
+mod unit_tests {
     use std::fs::File;
     use std::path::Path;
 

block/src/qcow/vec_cache.rs

@@ -135,7 +135,7 @@ impl<T: Cacheable> CacheMap<T> {
 }
 
 #[cfg(test)]
-mod tests {
+mod unit_tests {
     use super::*;
 
     struct NumCache(());

block/src/vhd.rs

@@ -117,7 +117,7 @@ pub fn is_fixed_vhd(f: &mut File) -> std::io::Result<bool> {
 }
 
 #[cfg(test)]
-mod tests {
+mod unit_tests {
     use std::fs::File;
     use std::io::{Seek, SeekFrom, Write};