Migrate pypa/gh-action-pypi-publish to a correct branch

[schalox]

pypa/gh-action-pypi-publish shows this warning, because we are still using its master branch:

Warning: You are using "pypa/gh-action-pypi-publish@master". The "master" branch of this project has been sunset and will not receive any updates, not even security bug fixes. Please, make sure to use a supported version. If you want to pin to v1 major version, use "pypa/gh-action-pypi-publish@release/v1". If you feel adventurous, you may opt to use use "pypa/gh-action-pypi-publish@unstable/v1" instead. A more general recommendation is to pin to exact tags or commit shas.

See the message here: https://github.com/nordhealth/sqs-poller/actions/runs/7785239717/job/21227366523#step:7:30
See the project's README.md for more details: https://github.com/pypa/gh-action-pypi-publish?tab=readme-ov-file#-master-branch-sunset-

We should move from the master branch to release/v1 or to a specific tag, to avoid any issues in the future.