Rename master branch to main

[MFraters]

After a discussion in the aspect bi-weekly meeting about switching the aspect master branch to main, we decided that it might be a good idea to first try this change with the world builder, because there are likely less issues and less users, making it a good testing ground. This is something which was on my mind for a while anyway, so I think this is a good opportunity to switch.

I will have to take a look at the tester, but I suspect that because the tester in through github, it should not be big issue. It may affect the coverage history, but I don't think that is much of an issue.

I will leave this issue open for a few days to see if there are any comments and I am planning to make the switch before the end of the week.

@gassmoeller Is there a similar issue in the aspect repository which could be linked here?

[MFraters]

And thanks for bringing this up during the meeting Rene!

[gassmoeller]

It was on my mind for the past months already. Created an ASPECT issue as well. See geodynamics/aspect#4383.

[MFraters]

I looked through the places where the word master appears, and I will need to update some things afterwards, but I don't think it will break anything important.

[MFraters]

And here is the advice github provides for updating local branches:

git branch -m master <BRANCH>
git fetch origin
git branch -u origin/<BRANCH> <BRANCH>
git remote set-head origin -a

[MFraters]

That is quite neat, after renaming it showed me this:

and here is the text

git branch -m master main
git fetch origin
git branch -u origin/main main
git remote set-head origin -a

[MFraters]

The update to main seems to have gone smoothly, and I think this issue can be closed. If any issues are encountered, feel free to reopen this issue.