Roll setup-dart (#3054)

diff --git a/.github/workflows/test.yaml b/.github/workflows/test.yaml
index 9c48813..100efc4 100644
--- a/.github/workflows/test.yaml
+++ b/.github/workflows/test.yaml
@@ -25,9 +25,9 @@
         sdk: [dev]
     steps:
       - uses: actions/checkout@v2
-      - uses: dart-lang/setup-dart@v0.1
+      - uses: dart-lang/setup-dart@v1.2
         with:
-          channel: ${{ matrix.sdk }}
+          sdk: ${{ matrix.sdk }}
       - id: install
         name: Install dependencies
         run: dart pub get
@@ -53,9 +53,9 @@
         shard: [0, 1, 2, 3, 4, 5, 6]
     steps:
       - uses: actions/checkout@v2
-      - uses: dart-lang/setup-dart@v0.1
+      - uses: dart-lang/setup-dart@v1.2
         with:
-          channel: ${{ matrix.sdk }}
+          sdk: ${{ matrix.sdk }}
       - name: Install dependencies
         run: dart pub get
       - name: Build snapshot