Document MigrateAPIVersion feature gate for kustomize-controller

Signed-off-by: Matheus Pimenta <matheuscscp@gmail.com>

Author: matheuscscp

content/en/flux/components/kustomize/options.md

@@ -59,5 +59,6 @@ please see the [bootstrap customization guide](/flux/installation/configuration/
 | `DisableStatusPollerCache`       | `true`        | Disables the cache of the status poller, which is used to determine the health of the resources applied by the controller. This may have a positive impact on memory usage on large clusters with many objects, at the cost of an increased number of direct API calls. |
 | `ExternalArtifact`               | `true`        | Enables support for the [ExternalArtifact](https://github.com/fluxcd/source-controller/blob/main/docs/spec/v1/externalartifacts.md) source type.                                                                                                                        |
 | `GroupChangeLog`                 | `false`       | Groups together kubernetes objects in log output. Reduces cardinality for Elasticsearch/Opensearch indexing                                                                                                                                                             |
+| `MigrateAPIVersion`              | `false`       | Migrates the API version referenced by the managed fields entries of in-cluster objects to the API version of the applied objects when they differ. Works around server-side apply dry-run failures like `field not declared in schema` after CRD upgrades.            |
 | `ObjectLevelWorkloadIdentity`    | `false`       | Enables the use of object-level workload identity for the controller.                                                                                                                                                                                                   |
 | `StrictPostBuildSubstitutions`   | `false`       | Controls whether the post-build substitutions should fail if a variable without a default value is declared in files but is missing from the input vars.                                                                                                                |