docs(rulesets): first iteration of shape of ruleset definition

for #732

docs/plugins/rulesets.md

@@ -0,0 +1,53 @@
+# Repository Rulesets
+
+See https://docs.github.com/en/rest/repos/rules#update-a-repository-ruleset for
+all available ruleset properties and a description of each.
+
+```yaml
+rulesets:
+  - name: prevent destruction of the default branch
+    target: branch
+    enforcement: active
+    conditions:
+      ref_name:
+        include:
+          - "~DEFAULT_BRANCH"
+    rules:
+      - type: deletion
+      - type: non_fast_forward
+
+  - name: verification must pass
+    target: branch
+    enforcement: active
+    conditions:
+      ref_name:
+        include:
+          - "~DEFAULT_BRANCH"
+    rules:
+      - type: required_status_checks
+        parameters:
+          required_status_checks:
+            - context: test
+              integration_id: 123456
+    bypass_actors:
+      - actor_id: 5
+        actor_type: RepositoryRole
+        bypass_mode: pull_request
+
+  - name: changes must be reviewed
+    target: branch
+    enforcement: active
+    conditions:
+      ref_name:
+        include:
+          - "~DEFAULT_BRANCH"
+    rules:
+      - type: pull_request
+        parameters:
+          required_approving_review_count: 1
+          require_code_owner_review: true
+    bypass_actors:
+      - actor_id: 654321
+        actor_type: Integration
+        bypass_mode: always
+```