Fix timezone naming convention in env_preferences (#5954)

As decided in #4350


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utils/env_preferences/src/apple.rs

@@ -152,7 +152,7 @@ pub fn get_system_calendars() -> Result<Vec<(String, String)>, RetrievalError> {
 }
 
 /// Get the current time zone of the system
-pub fn get_system_timezone() -> Result<String, RetrievalError> {
+pub fn get_system_time_zone() -> Result<String, RetrievalError> {
     // SAFETY: Returns the time zone currently used by the system
     // Returns an immutable reference to TimeZone object owned by us
     let timezone = unsafe { timezone::CFTimeZoneCopySystem() };

utils/env_preferences/src/windows.rs

@@ -36,7 +36,7 @@ pub fn get_system_calendars() -> Result<Vec<(String, String)>, RetrievalError> {
 }
 
 /// Get the current time zone of the system
-pub fn get_system_timezone() -> Result<String, RetrievalError> {
+pub fn get_system_time_zone() -> Result<String, RetrievalError> {
     let calendar = Globalization::Calendar::new()?;
     let timezone = calendar.GetTimeZone()?;
     Ok(timezone.to_string_lossy())

utils/env_preferences/tests/test.rs

@@ -68,7 +68,7 @@ mod linux_tests {
 #[cfg(target_os = "macos")]
 #[cfg(test)]
 mod macos_test {
-    use env_preferences::{get_locales, get_system_calendars, get_system_timezone};
+    use env_preferences::{get_locales, get_system_calendars, get_system_time_zone};
     use icu_locale::Locale;
 
     #[test]
@@ -111,15 +111,15 @@ mod macos_test {
 
     #[test]
     fn test_time_zone() {
-        let time_zone = get_system_timezone().unwrap();
+        let time_zone = get_system_time_zone().unwrap();
         assert!(!time_zone.is_empty(), "Couldn't retreive time_zone");
     }
 }
 
 #[cfg(target_os = "windows")]
 #[cfg(test)]
 mod windows_test {
-    use env_preferences::{get_locales, get_system_calendars, get_system_timezone};
+    use env_preferences::{get_locales, get_system_calendars, get_system_time_zone};
     use icu_locale::Locale;
 
     #[test]
@@ -155,7 +155,7 @@ mod windows_test {
 
     #[test]
     fn test_time_zone() {
-        let time_zone = get_system_timezone().unwrap();
+        let time_zone = get_system_time_zone().unwrap();
         assert!(!time_zone.is_empty(), "Couldn't retreive time_zone");
         assert!(time_zone.is_ascii(), "Invalid TimeZone format");
     }