Actions: Use main branch (#428)

Author: ryonakano

.github/workflows/main.yml

@@ -38,4 +38,4 @@ jobs:
 
     steps:
     - uses: actions/checkout@v4
-    - uses: elementary/actions/vala-lint@master
+    - uses: elementary/actions/vala-lint@main

.github/workflows/release.yml

@@ -10,7 +10,7 @@ jobs:
      if: github.event.pull_request.merged == true && true == contains(join(github.event.pull_request.labels.*.name), 'Release')
      steps:
      - uses: actions/checkout@v4
-     - uses: elementary/actions/release@master
+     - uses: elementary/actions/release@main
        env:
          GIT_USER_TOKEN: "${{ secrets.GIT_USER_TOKEN }}"
          GIT_USER_NAME: "elementaryBot"