### Godot version

4.1

### System information

Windows

### Issue description

Being able to have multiple cursors similarly to vscode is a great feature, however it's only possible to add carets, not remove them. By left clicking you can remove all extra cursors but you cannot remove a specific one so after selecting multiple lines a single missclick, you have to reselect them all again. Looking at the original pr there was a remove_caret function added so it would make sense to be able to remove carets when clicking again, like in vscode.

![image](https://github.com/godotengine/godot/assets/19669673/3867c00e-9faa-4429-9c6d-f2d6d3883044)


### Steps to reproduce

- Alt click to add multiple carets
- Alt click on the same position again
- Nothing happens

### Minimal reproduction project

N/A
} while (cc != quotation);
									} else if (cc == c) {
										stack++;
									} else if (cc == closec) {
										stack--;
									}
									if (stack == 0) {
										brace_matching.write[caret].close_match_line = i;
										brace_matching.write[caret].close_match_column = j;
										brace_matching.write[caret].close_matching = true;
										break;
									}
								}
								if (brace_matching.write[caret].close_match_line != -1) {
									break;
								}
							}
							if (!brace_matching.write[caret].close_matching) {
								brace_matching.write[caret].close_mismatch = true;
							}
						}
					}
				}
			}
			bool draw_placeholder = text.size() == 1 && text[0].is_empty() && ime_text.is_empty();
			
			String highlighted_text = get_selected_text(0);
			
			bool only_whitespaces_highlighted = highlighted_text.strip_edges().is_empty();
			HashMap<int, HashSet<int>> caret_line_wrap_index_map;