Batch Request Steps not guaranteed to retain insertion order

[Ndiritu]

Describe the bug

We store batch requests steps in a dictionary which doesn't guarantee insertion order when reading batch request steps.

When using dependsOn within OData Batch requests, the API expects that the dependency appears earlier in the array of requests.
Microsoft Graph fails with "Invalid dependency for request Id..."

Expected behavior

The developer dictates the order of batch request steps & that the order is retained during serialization. In case of an error, developer needs to adjust their order.

How to reproduce

Add batch request steps with different keys (UUIDs, ints etc) and test that insertion order is retained when calling GetBatchRequestContentAsync()

SDK Version

3.1.17

Latest version known to work for scenario above?

No response

Known Workarounds

No response

Debug output

Click to expand log

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### Configuration

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### Other information

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