[Hivemind] Create GithubSummaryTransformer class

[cyri113]

Part of the Github Vectorize (Summary). Please read this document before starting.

The following changes should be implemented in dags/hivemind_etl_helpers/src/db/github/transform.

Tasks

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1. Create a class GithubSummaryTransformer
2. Inherit from SummaryTransformer. See example.
3. Create a public method transform that transforms the summary to a llama-index document and add the required metadata. See details.
4. Create the required test cases

Note: file coverage should be 100%.

[cyri113]

Hi @FatemehVahabi could you please create one PR for all your changes? I'm a little confused with this.