object.relation(..) throws "Invalid key '...'" when beforeFind() trigger change the query

New Issue Checklist

• I am not disclosing a vulnerability.
• I am not just asking a question.
• I have searched through existing issues.
• I can reproduce the issue with the latest version of Parse Server.

Issue Description

Hi !

I have a beforeFind trigger that add a few restrictions on a child type, when executing parent.query().find() the server throw a Invalid key "$relatedTo"

Steps to reproduce

I have a Parent with a relation to a Child

Then:

// /cloud/index.js
  Parse.Cloud.beforeFind("Child", (req) => {
      const a = new Parse.Query("Child")
      const b = new Parse.Query("Child")

      a.equalTo('field', 'abcd')
      b.doesNotExist('field')

      return Parse.Query.and(req.query, Parse.Query.or(a, b)  )
})   

On the client

// client
const parent = new Parent()

await parent.relation('childs').query().find()

Actual Outcome

Error in mounted hook (Promise/async): "ParseError: 105 Invalid key name: $relatedTo"

Expected Outcome

An happy relation! 👪

Failing Test Case / Pull Request

It seems that reduceRelationKeys only checks for a Top level $or, and in my case, the top level operator is $and

This seems like it 'fixes' the issue :

  reduceRelationKeys(className, query, queryOptions) {
//    if (query['$or']) {
//      return Promise.all(query['$or'].map(aQuery => {
//        return this.reduceRelationKeys(className, aQuery, queryOptions);
//      }));
//    }
    for(const op of ['$or', '$and' , '$not']) {
      if (query[op]) {
        return Promise.all(query[op].map(aQuery => {
          return this.reduceRelationKeys(className, aQuery, queryOptions);
        }));
      }
    }
// ....

• 🤩 I submitted a PR with a fix and a test case.
• 🧐 I submitted a PR with a failing test case.

Environment

Server

• Parse Server version: 4.5.0
• Operating system: windows
• Local or remote host (AWS, Azure, Google Cloud, Heroku, Digital Ocean, etc): local

Database

• System (MongoDB or Postgres): mongo
• Database version: 4.4?
• Local or remote host (MongoDB Atlas, mLab, AWS, Azure, Google Cloud, etc): local

Client

• SDK (iOS, Android, JavaScript, PHP, Unity, etc): js
• SDK version: 3.1.0

Logs

Start with the reproduction in /cloud/index.js and the client relation query, then inspect reduceRelationKeys where nested $or, $and, and $not operators are handled. Reproduce the beforeFind query against the documented MongoDB setup and verify that parent.relation('childs').query().find() completes without the Invalid key name: $relatedTo error.