chore(main): release 3.15.0

[github-actions[bot]]

:robot: I have created a release beep boop

3.15.0 (2024-06-03)

Features

• dynamic backends clientCertificate with SecretStore fromBytes, rawbytes (#796) (7d2b7b7)
• support default timeout configurations for dynamic backends (#792) (4dfa8d7)

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[github-actions[bot]]

:robot: Release is at https://github.com/fastly/js-compute-runtime/releases/tag/v3.15.0 :sunflower: