### Godot version

v4.2.beta1.official [b1371806a]

### System information

Godot v4.2.beta1 - macOS 12.7.0 - Vulkan (Forward+) - dedicated AMD Radeon HD - FirePro D300 - Intel(R) Xeon(R) CPU E5-1620 v2 @ 3.70GHz (8 Threads)

### Issue description

When creating a plugin with a dot in the name in the project settings and leaving "Script Name" empty fails. Also, when a plugin folder is added via file system which contains a dot, information for that plugin cannot be be updated in the project settings.

Will be solved by: https://github.com/godotengine/godot/pull/83329

### Steps to reproduce

Create new plugin:

- Open project settings
- Click on "Create New Plugin" in the "Plugin" tab
- Choose a name with a dot in it (e.g., "my.plugin") and leave "Script Name" empty
- Create
- It will fail to create the plugin script

Update existing plugin:

- Add a plugin directory with a dot in the folder name (e.g., "my.plugin") in the file system
- Open project settings
- Click on the edit button in the "Plugin" tab for that plugin
- Change "Author" to some name
- Update
- Author was not changed in the table or in "plugin.cfg"

### Minimal reproduction project

[plugin_config_dialog.zip](https://github.com/godotengine/godot/files/12905755/plugin_config_dialog.zip)

script_edit->set_placeholder("\"plugin.gd\" -> res://addons/my_plugin/plugin.gd");
	script_edit->set_h_size_flags(Control::SIZE_EXPAND_FILL);
	grid->add_child(script_edit);
	
	
	Label *active_lb = memnew(Label);
	active_lb->set_text(TTR("Activate now?"));
	active_lb->set_horizontal_alignment(HORIZONTAL_ALIGNMENT_RIGHT);
	grid->add_child(active_lb);
	active_edit = memnew(CheckBox);
	active_edit->set_pressed(true);
	grid->add_child(active_edit);
	Control *spacing = memnew(Control);
	vbox->add_child(spacing);
	spacing->set_custom_minimum_size(Size2(0, 10 * EDSCALE));
	validation_panel = memnew(EditorValidationPanel);
	vbox->add_child(validation_panel);
	validation_panel->add_line(MSG_ID_PLUGIN, TTR("Plugin name is valid."));
	validation_panel->add_line(MSG_ID_SCRIPT, TTR("Script extension is valid."));
	validation_panel->add_line(MSG_ID_SUBFOLDER, TTR("Subfolder name is valid."));
	validation_panel->set_update_callback(callable_mp(this, &PluginConfigDialog::_on_required_text_changed));
	validation_panel->set_accept_button(get_ok_button());
	script_option_edit->connect("item_selected", callable_mp(validation_panel, &EditorValidationPanel::update).unbind(1));
	name_edit->connect("text_changed", callable_mp(validation_panel, &EditorValidationPanel::update).unbind(1));
	subfolder_edit->connect("text_changed", callable_mp(validation_panel, &EditorValidationPanel::update).unbind(1));
	script_edit->connect("text_changed", callable_mp(validation_panel, &EditorValidationPanel::update).unbind(1));
}
PluginConfigDialog::~PluginConfigDialog() {
}