Improve error logging for olm session creation failure

Summary:
This differential is created in response to the following linear issue: https://linear.app/comm/issue/ENG-4451/improve-logging-for-olm-session-creation-failure. Olm session creation failure is a seriious concern and current error handling does
not provide meaningful information for debugging purposes.

Test Plan: Delete olm sessions table from the database. Try to log in from mobile app. Ensure that meaningful logs are printed to the console.

Reviewers: tomek, ashoat

Reviewed By: tomek, ashoat

Differential Revision: https://phab.comm.dev/D8614

keyserver/src/creators/olm-session-creator.js

@@ -23,6 +23,11 @@ async function createOlmSession(
       callback,
     );
   } catch (e) {
+    console.warn(
+      `failed to create olm session of type: ${olmSessionType} ` +
+        `for user with cookie id: ${cookieID}`,
+      e,
+    );
     throw new ServerError('olm_session_creation_failure');
   }