`save-state` command is deprecated, causing warnings in CI

[JalonSolov]

Seeing this warning when using the vlang/setup-v action:

Run vlang/setup-v@v1 Warning: The save-state command is deprecated and will be disabled soon. Please upgrade to using Environment Files. For more information see: https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

The action needs to be updated.