Error when updating an existing object with context

[marcinjakubowski]

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

In cloud code, when trying to update an existing object in an afterSave trigger with a context set on call to save, an error is reported and update does not go through. Seems to be some sort of a regression to #6735.

Steps to reproduce

Use the following cloud code:

Parse.Cloud.afterSave('TestObject1', async (request) => {
    const TestObj2 = Parse.Object.extend('TestObject2');
    const query = new Parse.Query(TestObj2);
    const obj = await query.first();

    return obj.save(null, { useMasterKey: true, context: { op: 'auto' } })
});

1. Create a new class called TestObject2 and a new object of that class.
2. Create a new class callsed TestObject1 and a new object of that class.
3. afterSave trigger from cloud code above will trigger and fail with the error below.

Actual Outcome

Error is reported, object is not saved:

error: afterSave failed for TestObject1 for user undefined: 
  Error: {"message":"Invalid field name: _context.","code":105} {"className":"TestObject1","triggerType":"afterSave","error":{"message":"Invalid field name: _context.","code":105}}
warn: afterSave caught an errorInvalid field name: _context. {"code":105,"stack":"Error: Invalid field name: _context.\n    at handleError (/home/myak/src/github/parse-server/node_modules/parse/lib/node/RESTController.js:402:17)\n    at process._tickCallback (internal/process/next_tick.js:68:7)"}

Expected Outcome

Object is saved, context is available in beforeSave trigger on TestObject1.

Environment

Server

• Parse Server version: 4.3.0
• Operating system: Linux
• Local or remote host (AWS, Azure, Google Cloud, Heroku, Digital Ocean, etc): FILL_THIS_OUT

Database

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

Client

• SDK (iOS, Android, JavaScript, PHP, Unity, etc): n/a
• SDK version: n/a

[marcinjakubowski]

Sorry, something had to be wrong with my cache, I deleted my local repo, cloned again and it works flawlessly.