docs: show VEX cli pages + update config file page for VEX flags (#7244)

Author: DmitriyLewen

Diff for: docs/docs/references/configuration/config-file.md

@@ -276,6 +276,16 @@ vulnerability:
   # Default is empty
   ignore-status: 
     - end_of_life
+
+  # Same as '--vex'
+  # Default is empty
+  vex:
+    - path/to/vex/file
+    - repo
+
+  # Same as '--skip-vex-repo-update'
+  # Default is false
+  skip-vex-repo-update: true
 ```
 
 ## License Options

Diff for: mkdocs.yml

@@ -180,6 +180,12 @@ nav:
                   - SBOM: docs/references/configuration/cli/trivy_sbom.md
                   - Server: docs/references/configuration/cli/trivy_server.md
                   - Version: docs/references/configuration/cli/trivy_version.md
+                  - VEX:
+                      - VEX: docs/references/configuration/cli/trivy_vex.md
+                      - VEX Download: docs/references/configuration/cli/trivy_vex_repo_download.md
+                      - VEX Init: docs/references/configuration/cli/trivy_vex_repo_init.md
+                      - VEX List: docs/references/configuration/cli/trivy_vex_repo_list.md
+                      - VEX Repo: docs/references/configuration/cli/trivy_vex_repo.md
                   - VM: docs/references/configuration/cli/trivy_vm.md
               - Config file: docs/references/configuration/config-file.md
           - Modes: