### 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)

subfolder_edit->set_placeholder("\"my_plugin\" -> res://addons/my_plugin");
	subfolder_edit->set_tooltip_text(TTR("Optional. The folder name should generally use `snake_case` naming (avoid spaces and special characters).\nIf left empty, the folder will be named after the plugin name converted to `snake_case`."));
	subfolder_edit->set_h_size_flags(Control::SIZE_EXPAND_FILL);
	grid->add_child(subfolder_edit);
	
	Label *desc_lb = memnew(Label);
	desc_lb->set_text(TTR("Description:"));
	desc_lb->set_horizontal_alignment(HORIZONTAL_ALIGNMENT_RIGHT);
	grid->add_child(desc_lb);
	desc_edit = memnew(TextEdit);
	desc_edit->set_tooltip_text(TTR("Optional. This description should be kept relatively short (up to 5 lines).\nIt will display when hovering the plugin in the list of plugins."));
	desc_edit->set_custom_minimum_size(Size2(400, 80) * EDSCALE);
	desc_edit->set_line_wrapping_mode(TextEdit::LineWrappingMode::LINE_WRAPPING_BOUNDARY);
	desc_edit->set_h_size_flags(Control::SIZE_EXPAND_FILL);
	desc_edit->set_v_size_flags(Control::SIZE_EXPAND_FILL);
	grid->add_child(desc_edit);
	
	Label *author_lb = memnew(Label);
	author_lb->set_text(TTR("Author:"));
	author_lb->set_horizontal_alignment(HORIZONTAL_ALIGNMENT_RIGHT);
	grid->add_child(author_lb);
	author_edit = memnew(LineEdit);
	author_edit->set_placeholder("Godette");
	author_edit->set_tooltip_text(TTR("Optional. The author's username, full name, or organization name."));
	author_edit->set_h_size_flags(Control::SIZE_EXPAND_FILL);
	grid->add_child(author_edit);
	
	Label *version_lb = memnew(Label);
	version_lb->set_text(TTR("Version:"));
	version_lb->set_horizontal_alignment(HORIZONTAL_ALIGNMENT_RIGHT);