test: run A/B tests for feature branches

[bchalios]

Reason

We had only enabled the workflow for main and release branches.

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---

• This functionality cannot be added in rust-vmm.

[roypat]

just in case you didn't know, you'll also need to port this to the feature branches that already exist if you want them to trigger A/B runs

[bchalios]

just in case you didn't know, you'll also need to port this to the feature branches that already exist if you want them to trigger A/B runs

Yup, I'll rebase my branch :)