[feat] Support consumer client memory limit

[Gleiphir2769]

Master Issue: #927

Motivation

This is part of the work for PIP 74 in go client.

More details in #927 .

Modifications

• Consumer adds memory limit relate logic.

Verifying this change

• Make sure that the change passes the CI checks.

Documentation

• Does this pull request introduce a new feature? (yes / no)
• If yes, how is the feature documented? (not applicable / docs / GoDocs / not documented)

[Anonymitaet]

Hi @shibd, thanks for introducing this great feature!

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As we discussed just now, for the doc side:

✅ Pulsar feature matrix

I've ticked the box of "Memory Limits" for Go.

✅ Pulsar client docs

🌈 Collobration way

To add docs for it, feel free to choose your preferred method (either way works for me):

• You provide tech inputs to me. I'll write docs based on them and request your review. Or

• You submit a PR to the pulsar-site repo directly and request my review.

🌈 TO-DO tasks

1. Create a tab for Go and a topic named "Set memory limits" in work with clients. It should explain:

• What is it?
• How to use it? (e.g., any considerations? Sample code, etc)

2. This doc is only added to NEXT (submit a PR here) since this feature is server-independent.

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Feel free to reach out to me if you have questions. TIA!