Pin CI actions missed in previous PR

Author: jakebailey

.github/workflows/CI.yml

@@ -14,10 +14,10 @@ jobs:
         node-version: [12.x, 14.x, 16.x]
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2.7.0
 
       - name: Use node version ${{ matrix.node-version }}
-        uses: actions/setup-node@v1
+        uses: actions/setup-node@f1f314fca9dfce2769ece7d933488f076716723e # v1.4.6
         with:
           node-version: ${{ matrix.node-version }}