pypi is creating packages on PR creation

[shimwell]

The github actions is being triggered on the creation of new PR

This should be done on merges into openmc version

perhaps this part of the github action needs changing

neutronics_material_maker/.github/workflows/python-publish.yml

Lines 6 to 12 in 3f36e88

	on:
	pull_request:
	branches:
	- openmc_version
	push:
	branches:
	- openmc_version

[shimwell]

Tried to fix this in the latest PR #67

[shimwell]

github actions has been updated