add: equals method to aggregation and aggregation ops

[therealansh]

Closes #4692 , Sorry for being the impatient one 😬 but would love to contribute.

• Aggregation
• AggregationPipeline
• AggregationOperations:
  • AddFieldsOperation
  • BasicAggregation
  • BucketAutoOperation

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[mp911de]

Sorry for being the impatient one 😬 but would love to contribute.

Thanks a lot for your contribution, we're happy to welcome contributions, also from impatient ones 🤩

While at it, we have a couple more AggregationOperations. Care to extend the pull request by adding equals/hashCode methods to the remaining types as well? That would greatly improve the duration until we can merge your pull request.

[therealansh]

@mp911de was on it already, thats why added a checklist to the PR summary, will extend this PR to cover those as well
thanks 🙌🏽