Update documentation around `architecture` field to include arm64

[michael-myers]

Description:
In the setup-python README and code comments in action.yml the architecture field only mentions x86 and x64, but elsewhere, GitHub Actions documentation says arm64 is a supported architecture across all GitHub-provided Actions. It seems like that is true, but the documentation here hasn't been updated.

If not supplying the architecture field, will setup-python still default to x64 even on an arm64 host? Because it looks like it will default to the arch of the host OS.

Action version:
v5.2.0

Platform:

• Ubuntu
• macOS
• Windows

It seems GitHub Actions provides hosted arm64 runners for all three platforms.

Runner type:

• Hosted
• Self-hosted

Tools version:
n/a, this is about documentation

Repro steps:
n/a, this is about documentation

Expected behavior:
n/a, this is about documentation

Actual behavior:
n/a, this is about documentation

[priyagupta108]

Hi @michael-myers 👋,
Thank you for pointing out the discrepancy in the documentation regarding the architecture field.
To clarify, when the architecture field is not specified, the action defaults to the host OS architecture, which includes arm64 for arm64 hosts.
We will update the documentation accordingly. If you have any additional insights or spot other documentation gaps, please let us know.

[priya-kinthali]

Hello @michael-myers 👋,
We have recently merged PR #965, which updates the README and action.yml to include arm64 support in the architecture field.
Please check the updated documentation. We will now proceed to close this issue. If you have any further questions or concerns, please feel free to let us know.
Thank you!

[michael-myers]

Looks good to me, and thank you for the quick resolution! 👍🏻