CI: Hashpin sensitive actions and install dependabot (#226)

.github/dependabot.yml

@@ -0,0 +1,11 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    groups:
+      github-actions:
+        patterns:
+          - "*"
+

.github/workflows/codeql.yml

@@ -46,11 +46,11 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v3
+      uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3.6.0
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v2
+      uses: github/codeql-action/init@689fdc5193eeb735ecb2e52e819e3382876f93f4 # v2.22.6
       with:
         config-file: ./.github/codeql/codeql-configuration.yml
         languages: ${{ matrix.language }}
@@ -65,7 +65,7 @@ jobs:
     # Autobuild attempts to build any compiled languages (C/C++, C#, Go, Java, or Swift).
     # If this step fails, then you should remove it and run the build manually (see below)
     - name: Autobuild
-      uses: github/codeql-action/autobuild@v2
+      uses: github/codeql-action/autobuild@689fdc5193eeb735ecb2e52e819e3382876f93f4 # v2.22.6
 
     # ℹ️ Command-line programs to run using the OS shell.
     # 📚 See https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsrun
@@ -78,6 +78,6 @@ jobs:
     #     ./location_of_script_within_repo/buildscript.sh
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v2
+      uses: github/codeql-action/analyze@689fdc5193eeb735ecb2e52e819e3382876f93f4 # v2.22.6
       with:
         category: "/language:${{matrix.language}}"

.github/workflows/publish.yaml

@@ -11,8 +11,8 @@ jobs:
   publish-npm:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      - uses: actions/setup-node@v1
+      - uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2.7.0
+      - uses: actions/setup-node@f1f314fca9dfce2769ece7d933488f076716723e # v1.4.6
         with:
           node-version: 14
           registry-url: https://registry.npmjs.org/