fix warnings

backend/src/main/scala/com/softwaremill/bootzooka/infrastructure/DB.scala

@@ -27,7 +27,7 @@ class DB(dataSource: DataSource & Closeable) extends Logging with AutoCloseable:
   /** Runs `f` in a transaction. The transaction is commited if the result is a [[Right]], and rolled back otherwise. */
   def transactEither[E, T](f: DbTx ?=> Either[E, T])(using IO): Either[E, T] =
     try com.augustnagro.magnum.transact(transactor)(Right(f.fold(e => throw LeftException(e), identity)))
-    catch case e: LeftException[E] => Left(e.left)
+    catch case e: LeftException[?] => Left(e.asInstanceOf[LeftException[E]].left)
 
   /** Runs `f` in a transaction. The result cannot be an `Either`, as then [[transactEither]] should be used. The transaction is commited if
     * no exception is thrown.

backend/src/main/scala/com/softwaremill/bootzooka/security/ApiKeyService.scala

@@ -26,4 +26,3 @@ class ApiKeyService(apiKeyModel: ApiKeyModel, idGenerator: IdGenerator, clock: C
   def invalidateAllForUser(userId: Id[User])(using DbTx): Unit =
     logger.debug(s"Invalidating all api keys for user $userId")
     apiKeyModel.deleteAllForUser(userId)
-

backend/src/main/scala/com/softwaremill/bootzooka/security/Auth.scala

@@ -7,8 +7,8 @@ import com.softwaremill.bootzooka.logging.Logging
 import com.softwaremill.bootzooka.user.User
 import com.softwaremill.bootzooka.util.*
 import com.softwaremill.bootzooka.util.Strings.Id
-import ox.{IO, either, sleep}
 import ox.either.{fail, ok}
+import ox.{IO, sleep}
 
 import java.security.SecureRandom
 import java.time.Instant
@@ -20,7 +20,7 @@ class Auth[T](authTokenOps: AuthTokenOps[T], db: DB, clock: Clock) extends Loggi
   private val random = SecureRandom.getInstance("NativePRNGNonBlocking")
 
   /** Authenticates using the given authentication token. If the token is invalid, a [[Fail.Unauthorized]] error is returned. Otherwise,
-    * returns the id of the authenticated user  .
+    * returns the id of the authenticated user .
     */
   def apply(id: Id[T])(using IO): Either[Fail.Unauthorized, Id[User]] =
     db.transact(authTokenOps.findById(id)) match {