prysm/PULL_REQUEST_TEMPLATE.md

TODO(you): choose "part of" or "resolves" and the associated github issue #.

[Part of|Resolves] #531

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Description

TODO(you): Write why you are making the changes in this pull request.

TODO(you): Write a summary of the changes you are making.

TODO(you): Link anything that would be helpful or relevant to the reviewers.