update(docs): add FALCOCTL_ARTIFACT_NOVERIFY

Signed-off-by: Luca Guerra <[email protected]>

README.md

@@ -373,6 +373,7 @@ This is the list of the environment variable that `falcoctl` will use:
 | `FALCOCTL_ARTIFACT_INSTALL_REFS`          | `ref1;ref2`                                                      |
 | `FALCOCTL_ARTIFACT_INSTALL_RULESFILESDIR` | `rules-directory-path`                                           |
 | `FALCOCTL_ARTIFACT_INSTALL_PLUGINSDIR`    | `plugins-directory-path`                                         |
+| `FALCOCTL_ARTIFACT_NOVERIFY`              |                                                                  | 
 
 Please note that when passing multiple arguments via an environment variable, they must be separated by a semicolon. Moreover, multiple fields of the same argument must be separated by a comma.