docs: add example of creating whitelist of checks (#7821)

Signed-off-by: nikpivkin <nikita.pivkin@smartforce.io>

docs/docs/configuration/filtering.md

@@ -477,13 +477,13 @@ ignore {
 ```
 
 ```bash
-trivy image --ignore-policy contrib/example_policy/basic.rego centos:7
+trivy image --ignore-policy examples/ignore-policies/basic.rego centos:7
 ```
 
 For more advanced use cases, there is a built-in Rego library with helper functions that you can import into your policy using: `import data.lib.trivy`.
 More info about the helper functions are in the library [here](https://github.com/aquasecurity/trivy/tree/{{ git.tag }}/pkg/result/module.go).
 
-You can find more example checks [here](https://github.com/aquasecurity/trivy/tree/{{ git.tag }}/pkg/result/module.go)
+You can create a whitelist of checks using Rego, see the detailed [example](https://github.com/aquasecurity/trivy/tree/{{ git.tag }}/examples/ignore-policies/whitelist.rego). Additional examples are available [here](https://github.com/aquasecurity/trivy/tree/{{ git.tag }}/examples/ignore-policies).
 
 ### By Vulnerability Exploitability Exchange (VEX)
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examples/ignore-policies/whitelist.rego

@@ -0,0 +1,13 @@
+package trivy
+
+import rego.v1
+
+allowed_checks := {
+    "AVD-AWS-0089"
+}
+
+default ignore := false
+
+ignore if not is_check_allowed
+
+is_check_allowed if input.AVDID in allowed_checks