Rename git master branch to main

[jonahgraham]

I would like to rename the master branch to main. This is current best practice and would make it consistent with the main CDT git repo.

Any objections?

[ruspl-afed]

Any changes that reduce maintenance costs are welcome.

[jonahgraham]

Request put into https://gitlab.eclipse.org/eclipsefdn/helpdesk/-/issues/5430

[jonahgraham]

It can be done with self-service. Thomas did it for us this time in eclipse-cdt/.eclipsefdn#10

[jonahgraham]

The default branch has been renamed!
master is now named main

If you have a local clone, you can update it by running the following commands.

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

You should also see the above message on your next visit to https://github.com/eclipse-cdt/cdt-lsp