chore: migrate to setup-github-token action everywhere

[erikburt]

All these actions used the old way of getting a GATI token, this updates them to use the setup-github-token action.

Old way is manually calling:

1. Assume aws credentials
2. GATI lambda action
3. Update git config

setup-github-token does all of that for you.

Motivation

1. Removes references to chainlink-github-actions repo, where GATI action used to be stored.
2. Modernizes these to use the standard setup-github-token
3. Updates the resulting GATI action to the node24 version

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DX-777 / DX-3617