docs(README): bump version to 0.8.7

[Chaitanya-Keyal]

Description

Bumped all version references in the README to 0.8.7!

Additional Information

• To be merged after the release is signed and tagged.

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This pull request is categorized as a:

• Documentation

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Checklist

I ran pytest locally

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I included screenshots of any new or modified screens

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I added or updated tests

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I tested this PR hands-on on the following platform(s):

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I have reviewed these notes:

• Keep your changes limited in scope.
• If you uncover other issues or improvements along the way, ideally submit those as a separate PR.
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• I understand