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**Description**

<!-- A short description of your feature -->
This feature requests a way to support custom views in plugins without any menu. Right now, all the views listed in `AirflowPlugin.appbuilder_views` are added with menu to the appbuilder.

**Use case / motivation**
In a custom plugin I built, I need to add a distinct view for details of custom operator. Then I use the `BaseOperator.operator_extra_links` to link this new UI view with the task links.
However, this view has no need to show in the airflow menu, but rather should be shown in UI similarly to `views.DagModelView`. That is, the view should be added to flask appbuilder using `appbuilder.add_view_no_menu` call but right now all the views in `AirflowPlugin.appbuilder_views` are added by calling `appbuilder.add_view`

**What do you want to happen?**

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step back and describe what you are trying to achieve.

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Maybe if "name" is missing in the dict in `AirflowPlugin.appbuilder_views` list, then when integrating plugin to flask app context, it'll just call:
```python
appbuilder.add_view_no_menu(v["view"])
```
otherwise the default behavior.

tests/plugins/test_plugin.py
pass
class PluginOperator(BaseOperator):
    pass
class PluginSensorOperator(BaseSensorOperator):
    pass
class PluginExecutor(BaseExecutor):
    pass
def plugin_macro():
    pass
class PluginTestAppBuilderBaseView(AppBuilderBaseView):
    default_view = "test"
    @expose("/")
    def test(self):
        return self.render_template("test_plugin/test.html", content="Hello galaxy!")
v_appbuilder_view = PluginTestAppBuilderBaseView()
v_appbuilder_package = {"name": "Test View", "category": "Test Plugin", "view": v_appbuilder_view}
appbuilder_mitem = {
    "name": "Google",
    "category": "Search",
    "category_icon": "fa-th",
    "href": "https://www.google.com",
}
bp = Blueprint(
    "test_plugin",
    __name__,
    template_folder='templates',  
    static_folder='static',
    static_url_path='/static/test_plugin',
)
class AirflowTestPlugin(AirflowPlugin):