Rename test modules to tests

… for consistency.

crates/ruma-client-api/src/membership/joined_members.rs

@@ -84,7 +84,7 @@ pub mod v3 {
     }
 
     #[cfg(test)]
-    mod test {
+    mod tests {
         use ruma_common::mxc_uri;
         use serde_json::{from_value as from_json_value, json};
 

crates/ruma-common/src/events/secret/request.rs

@@ -133,7 +133,7 @@ pub enum SecretName {
 }
 
 #[cfg(test)]
-mod test {
+mod tests {
     use assert_matches2::assert_matches;
     use serde_json::{from_value as from_json_value, json, to_value as to_json_value};
 

crates/ruma-federation-api/src/transactions/edu.rs

@@ -313,7 +313,7 @@ impl SigningKeyUpdateContent {
 }
 
 #[cfg(test)]
-mod test {
+mod tests {
     use assert_matches2::assert_matches;
     use js_int::uint;
     use ruma_common::{events::ToDeviceEventType, room_id, user_id};

crates/ruma-identity-service-api/src/lookup.rs

@@ -28,7 +28,7 @@ pub enum IdentifierHashingAlgorithm {
 }
 
 #[cfg(test)]
-mod test {
+mod tests {
     use super::IdentifierHashingAlgorithm;
 
     #[test]