Bump actions/checkout from 4.1.6 to 4.1.7 (grpc#719)

Author: dependabot[bot]

.github/workflows/dart.yml

@@ -18,7 +18,7 @@ jobs:
       matrix:
         sdk: [3.2.0, dev]
     steps:
-      - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29
+      - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332
       - uses: dart-lang/setup-dart@f0ead981b4d9a35b37f30d36160575d60931ec30
         with:
           sdk: ${{ matrix.sdk }}
@@ -70,7 +70,7 @@ jobs:
           - os: macos-latest
             platform: chrome
     steps:
-      - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29
+      - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332
       - uses: dart-lang/setup-dart@f0ead981b4d9a35b37f30d36160575d60931ec30
         with:
           sdk: ${{ matrix.sdk }}