docs: adde instructions how to work with ignore_difference

Signed-off-by: leonsteinhaeuser <[email protected]>

README.md

@@ -73,6 +73,7 @@ No modules.
 | <a name="input_application_name_suffix"></a> [application\_name\_suffix](#input\_application\_name\_suffix) | Optional suffix to add to the application name. This is useful if you want to deploy the same application multiple times to the same cluster. The suffix is added to the application name after the cluster name. e.g. prometheus-staging-<suffix>. ArgoCD based gotemplating is supported. e.g. {{ index .path.segments 2 }} | `string` | `null` | no |
 | <a name="input_generator"></a> [generator](#input\_generator) | The generator configuration. Only one generator can be used at a time. | <pre>object({<br>    git = optional(object({<br>      repo_url = string<br>      revision = string<br>      files    = optional(list(string))<br>      directories = optional(list(object({<br>        path    = string<br>        exclude = bool<br>      })))<br>    }))<br>    pull_request = optional(list(object({<br>      requeue_after_seconds = number<br>      repo                  = string<br>      labels                = list(string)<br>    })))<br>  })</pre> | n/a | yes |
 | <a name="input_generator_segment_index_overwrite"></a> [generator\_segment\_index\_overwrite](#input\_generator\_segment\_index\_overwrite) | Optional generator setting to override the index path segment during path selection. This option should only be set if generator.git.directories is used. Otherwise it should be left empty as it may affect the behavior. If this option is set in combination with generator.git.directories and your repository contains the cluster folder name in its root directory, this option should be set to 0. In all other cases, this option should reflect the index segment level to the directory corresponding to the cluster name. | `number` | `null` | no |
+| <a name="input_ignore_difference"></a> [ignore\_difference](#input\_ignore\_difference) | A list of object kinds to ignore during the diff process. This is useful if you want to ignore certain differences between the application set and the cluster. e.g. if you want to ignore differences in the namespace labels. | <pre>list(object({<br>    group               = optional(string)<br>    jq_path_expressions = optional(list(string))<br>    json_pointers       = optional(list(string))<br>    kind                = optional(string)<br>    name                = optional(string)<br>    namespace           = optional(string)<br>  }))</pre> | `[]` | no |
 | <a name="input_labels"></a> [labels](#input\_labels) | Labels to apply to the application set | `map(string)` | `{}` | no |
 | <a name="input_manifest_source"></a> [manifest\_source](#input\_manifest\_source) | n/a | <pre>object({<br>    helm = optional(object({<br>      chart           = string<br>      repo_url        = string<br>      target_revision = string<br>      release_name    = string<br>    }))<br>    directory = optional(object({<br>      repo = object({<br>        url      = string<br>        revision = string<br>        path     = string<br>      })<br>      glob_path = optional(string)<br>    }))<br>  })</pre> | n/a | yes |
 | <a name="input_name"></a> [name](#input\_name) | The name of the application set | `string` | n/a | yes |