Fix Firestore SDK not limiting results when given limit(0)

[liu-husong]

Description

Opening this PR to sense check if this can be worked on to get merged. This PR fixes #2461 where the Firestore SDK doesn't seem to apply the limit clause when limit(0) is given.

Impact

The change should allow the Firestore SDK to handle limit(0) properly, i.e., returning an empty array as expected.

Testing

Unit test added. But I'm not familiar with the codebase so I'm not sure if that alone is sufficient.

Additional Information

Checklist

• Make sure to open an issue as a bug/issue before writing your code! That way we can discuss the change, evaluate designs, and agree on the general idea
• Ensure the tests and linter pass
• Code coverage does not decrease
• Appropriate docs were updated
• Appropriate comments were added, particularly in complex areas or places that require background
• No new warnings or issues will be generated from this change

Fixes #2461 🦕

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