chore(deps): pin dependencies

.github/workflows/rebase.yml

@@ -11,12 +11,12 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout the latest code
-        uses: actions/[email protected]
+        uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f # v2.3.4
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
           fetch-depth: 0 # otherwise, you will fail to push refs to dest repo
 
       - name: Automatic Rebase
-        uses: cirrus-actions/[email protected]
+        uses: cirrus-actions/rebase@c473b716e3fcde0c6bf67416e2c2882830ad40f6 # 1.5
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/test.yml

@@ -56,16 +56,16 @@ jobs:
             os: ubuntu-20.04
     steps:
       - name: Checkout source
-        uses: actions/[email protected]
+        uses: actions/checkout@2036a08e25fa78bbd946711a407b529a0a1204bf # v2.3.2
 
       - name: Setup cache
-        uses: actions/[email protected]
+        uses: actions/cache@c64c572235d810460d0d6876e9c705ad5002b353 # v2.1.6
         with:
           key: ${{ github.job }}-${{ matrix.elixir }}-${{ matrix.otp }}-${{ hashFiles('mix.lock') }}-1
           path: _build
 
       - name: Install runtime
-        uses: erlef/[email protected]
+        uses: erlef/setup-beam@2f0cc07b4b9bea248ae098aba9e1a8a1de5ec24c # v1.17.5
         with:
           elixir-version: ${{ matrix.elixir }}
           otp-version: ${{ matrix.otp }}