fix(alias): encode path again to match the alias in database

Before, the encoded path was sent to the database layer.
It is strange that we decode, encode and decode it again, can't see
the reason for it now. We may try not to encode it at all in the future.

packages/server/src/schema/uuid/abstract-uuid/resolvers.ts

@@ -610,7 +610,7 @@ async function resolveIdFromAlias(
     return await resolveIdFromUsername(usernameMatch.groups.username, context)
   }
 
-  cleanPath = cleanPath.slice(1)
+  cleanPath = decodePath(cleanPath.slice(1))
   // The following check is to avoid DB lookups for paths that we know do
   // not belong to UUIDs. This is a performance optimization.
   // Original code see https://github.com/serlo/database-layer/blob/71b80050ecda63d616ab34eda0fa1143cb9e3ddc/server/src/alias/model.rs#L17-L63