bump actions/checkout from 5 to 6

Author: deminy

.github/workflows/ci.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-22.04
     steps:
       - name: Checkout php-bsdiff
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
         with:
@@ -28,7 +28,7 @@ jobs:
     runs-on: macos-15
     steps:
       - name: Checkout php-bsdiff
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
         with:
@@ -63,7 +63,7 @@ jobs:
     runs-on: ${{matrix.os}}
     steps:
       - name: Checkout php-bsdiff
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Setup PHP
         id: setup-php
         uses: php/setup-php-sdk@v0.11