Handle possible list types for batched data_loader implementation of `@grpc`

[meskill]

In some cases batched request could be resolved to multiple values for every entry of the batched parent value. The logic is already implemented for the @http dataloader depending on the type of the field. See https://github.com/tailcallhq/tailcall/blob/23a56b4a980ad0df84cfb7c4b7d19467dccc2e9d/src/core/http/data_loader.rs#L45-L49 for reference.

Implement support for list types for the @grpc batched request

[tusharmath]

/bounty $100

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💎 $100 bounty • Tailcall Inc.

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Attempt	Started (GMT+0)	Solution
🔴 @ssddOnTop	Sep 24, 2024, 4:02:54 PM	WIP

[algora-pbc[bot]]

@ssddOnTop: Reminder that in 1 days the bounty will become up for grabs, so please submit a pull request before then 🙏

[algora-pbc[bot]]

The bounty is up for grabs! Everyone is welcome to /attempt #2891 🙌

[github-actions[bot]]

Action required: Issue inactive for 30 days. Status update or closure in 7 days.