Add zizmor GHA workflow and solve findings

.github/dependabot.yml

@@ -5,3 +5,5 @@ updates:
     directory: /
     schedule:
       interval: daily
+    cooldown:
+      default-days: 7

.github/workflows/add_to_project.yml

@@ -8,13 +8,14 @@ on:
     types:
       - opened
 
+permissions: {}
 
 jobs:
   add-to-project:
     name: Add to project
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/add-to-project@v2.0.0
+      - uses: actions/add-to-project@5afcf98fcd03f1c2f92c3c83f58ae24323cc57fd # v2.0.0
         with:
           project-url: https://github.com/orgs/trailofbits/projects/12
           github-token: ${{ secrets.ADD_TO_PROJECT_PAT }}

.github/workflows/tests.yml

@@ -9,6 +9,8 @@ on:
   pull_request:
     branches: [ master ]
 
+permissions: {}
+
 jobs:
   build:
 
@@ -20,11 +22,12 @@ jobs:
     runs-on: ${{ matrix.os }}
 
     steps:
-    - uses: actions/checkout@v6.0.2
+    - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       with:
         submodules: recursive
+        persist-credentials: false
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v6
+      uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6.2.0
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install Python Dependencies
@@ -33,7 +36,7 @@ jobs:
         pip install setuptools
         pip install .[dev]
     - name: Scan with pip-audit
-      uses: trailofbits/gh-action-pip-audit@v1.1.0
+      uses: trailofbits/gh-action-pip-audit@1220774d901786e6f652ae159f7b6bc8fea6d266 # v1.1.0
     - name: Lint with flake8
       run: |
         # stop the build if there are Python syntax errors or undefined names

.github/workflows/zizmor.yml

@@ -0,0 +1,24 @@
+name: GitHub Actions Security Analysis with zizmor 🌈
+
+on:
+  push:
+    branches: ["main", "master"]
+  pull_request:
+    branches: ["**"]
+
+permissions: {}
+
+jobs:
+  zizmor:
+    name: Run zizmor 🌈
+    runs-on: ubuntu-latest
+    permissions:
+      security-events: write # Required for upload-sarif (used by zizmor-action) to upload SARIF files.
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+
+      - name: Run zizmor 🌈
+        uses: zizmorcore/zizmor-action@5f14fd08f7cf1cb1609c1e344975f152c7ee938d # v0.5.6