Parse Server should return consistent error messages

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

The Parse Server should return consistent error messages. However, it is returning a message field when an internal error occurs, see:

https://github.com/parse-community/parse-server/blob/d8dc524c08036b2f326730e1ed214ed7a76141cb/src/middlewares.js#L375-L378

However, if you look at the other returns in:

https://github.com/parse-community/parse-server/blob/d8dc524c08036b2f326730e1ed214ed7a76141cb/src/middlewares.js#L364

and

https://github.com/parse-community/parse-server/blob/d8dc524c08036b2f326730e1ed214ed7a76141cb/src/middlewares.js#L368

Steps to reproduce

Sorry, but I don't know how to reproduce it consistently.

Actual Outcome

{ 
   "code": 1, 
   "message": "Internal server error." 
}

Expected Outcome

{ 
   "code": 1, 
   "error": "Internal server error."
}

Failing Test Case / Pull Request

• 🤩 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: Linux
• Local or remote host (AWS, Azure, Google Cloud, Heroku, Digital Ocean, etc): Both

Database

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

Client

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

Logs

Not applicable

Read src/middlewares.js at the referenced lines 364, 368, and 375-378, comparing the internal-error response with the other error responses. Confirm that the internal-error response uses the expected error field and verify the resulting JSON response against the issue's expected outcome.