ci: use main branch

Author: gvolpe

.github/workflows/home.yml

@@ -4,7 +4,7 @@ on:
   pull_request:
   push:
     branches:
-      - master
+      - main
     paths-ignore:
       - 'GNOME.md'
       - 'README.md'

.github/workflows/nixos.yml

@@ -6,7 +6,7 @@ on:
       - 'home/**'
   push:
     branches:
-      - master
+      - main
     paths-ignore:
       - 'GNOME.md'
       - 'README.md'

.github/workflows/update-metals.yml

@@ -28,7 +28,7 @@ jobs:
           committer: GitHub <noreply@github.com>
           author: ${{ github.actor }} <${{ github.actor }}@users.noreply.github.com>
           token: ${{ secrets.REPO_GITHUB_TOKEN }}
-          base: master
+          base: main
           branch: update/metals-${{ steps.fetcher.outputs.metals_version }}
           delete-branch: true
           commit-message: "Update Metals to ${{ steps.fetcher.outputs.metals_version }}"