PYTHON-5711 Add zizmor config and workflow (#96)

Author: blink1073

.github/workflows/zizmor.yml

@@ -0,0 +1,21 @@
+name: GitHub Actions Security Analysis with zizmor 🌈
+
+on:
+  push:
+    branches: ["master"]
+  pull_request:
+    branches: ["**"]
+
+jobs:
+  zizmor:
+    name: zizmor latest via Cargo
+    runs-on: ubuntu-latest
+    permissions:
+      security-events: write
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v6
+        with:
+          persist-credentials: false
+      - name: Run zizmor 🌈
+        uses: zizmorcore/zizmor-action@135698455da5c3b3e55f73f4419e481ab68cdd95 # v0.4.1

.github/zizmor.yml

@@ -0,0 +1,7 @@
+rules:
+  unpinned-uses:
+    config:
+      policies:
+        actions/*: ref-pin
+        mongodb-labs/drivers-github-tools/*: ref-pin
+        mongodb-labs/drivers-evergreen-tools: ref-pin