fix(query-builder): make QBFilterQuery type more strict

This type was supposed to be accepting only objects, but due to the `FilterQuery` supporting
naked primary keys, it also mistakenly allowed passing strings.

One place where this was a common issue was the `cond` parameter of `qb.leftJoin()`, which
only accepts object conditions.

packages/core/src/typings.ts

@@ -109,7 +109,7 @@ export type FilterQuery<T> =
   | NonNullable<ExpandScalar<Primary<T>>>
   | NonNullable<EntityProps<T> & OperatorMap<T>>
   | FilterQuery<T>[];
-export type QBFilterQuery<T = any> = FilterQuery<T> | Dictionary;
+export type QBFilterQuery<T = any> = ObjectQuery<T> | Dictionary;
 
 export interface IWrappedEntity<
   T,