Add dependabot (#105)

* Add dependabot

* Use version numbers for all actions

.github/dependabot.yml

@@ -0,0 +1,7 @@
+# https://docs.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/" # Location of package manifests
+    schedule:
+      interval: "monthly"

.github/workflows/CI.yml

@@ -34,16 +34,7 @@ jobs:
         with:
           version: ${{ matrix.version }}
           arch: ${{ matrix.arch }}
-      - uses: actions/cache@v1
-        env:
-          cache-name: cache-artifacts
-        with:
-          path: ~/.julia/artifacts
-          key: ${{ runner.os }}-test-${{ env.cache-name }}-${{ hashFiles('**/Project.toml') }}
-          restore-keys: |
-            ${{ runner.os }}-test-${{ env.cache-name }}-
-            ${{ runner.os }}-test-
-            ${{ runner.os }}-
+      - uses: julia-actions/cache@v1
       - uses: julia-actions/julia-buildpkg@v1
       - uses: julia-actions/julia-runtest@v1
         with:
@@ -54,7 +45,7 @@ jobs:
         if: matrix.version == '1' && matrix.os == 'ubuntu-latest'
         with:
           file: lcov.info
-      - uses: coverallsapp/github-action@master
+      - uses: coverallsapp/github-action@v2
         if: matrix.version == '1' && matrix.os == 'ubuntu-latest'
         with:
             github-token: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/Format.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: julia-actions/setup-julia@latest
+      - uses: julia-actions/setup-julia@v1
         with:
           version: 1
       - name: Format code

.github/workflows/IntegrationTest.yml

@@ -27,7 +27,7 @@ jobs:
         with:
           version: 1
           arch: x64
-      - uses: julia-actions/julia-buildpkg@latest
+      - uses: julia-actions/julia-buildpkg@v1
       - name: Clone Downstream
         uses: actions/checkout@v2
         with: