fix: update GitHub Actions workflow to use 'main' branch instead of 'master'

Author: myhloli

.github/workflows/python-package.yml

@@ -18,7 +18,7 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
         with:
-          ref: master
+          ref: main
           fetch-depth: 0
 
       - name: Set up Python
@@ -52,7 +52,7 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ secrets.RELEASE_TOKEN }}
         run: |
-          git push origin HEAD:master
+          git push origin HEAD:main
 
   check-install:
     needs: [ update-version ]
@@ -66,7 +66,7 @@ jobs:
     - name: Checkout code
       uses: actions/checkout@v4
       with:
-        ref: master
+        ref: main
         fetch-depth: 0
 
     - name: Verify version.py
@@ -97,7 +97,7 @@ jobs:
     - name: Checkout code
       uses: actions/checkout@v4
       with:
-        ref: master
+        ref: main
         fetch-depth: 0
 
     - name: Install wheel