Auto bounds breaks link_axis and link_cursor

**Describe the bug**

While auto bounds is active `link_axis` and `link_cursor` does not work if the plot data for the different plots have a different width.

The linking works if the user zoom's in, but when the user double clicks to enable auto bounds the plots are unaligned again.

**To Reproduce**

Run the following example:

```rs
use eframe::egui;
use egui_plot::Line;

fn main() -> eframe::Result {
let native_options = eframe::NativeOptions::default();

eframe::run_simple_native("UnalignedPlots", native_options, move |ctx, _frame| {
egui::CentralPanel::default().show(ctx, |ui| {
let plot_height = ui.available_height() / 2.0;

egui_plot::Plot::new("Plot1")
.height(plot_height)
.link_axis("plot_axis", [true, false])
.link_cursor("plot_cursor", [true, false])
.show(ui, |ui| {
ui.line(Line::new(vec![[0.0, 1.0], [10.0, 0.5]]));
});

egui_plot::Plot::new("Plot2")
.height(plot_height)
.link_axis("plot_axis", [true, false])
.link_cursor("plot_cursor", [true, false])
.show(ui, |ui| {
ui.line(Line::new(vec![[5.0, 0.5], [7.0, 1.0]]));
});
});
})
}
```

Cargo.toml:

```toml
[package]
name = "unaligned_plots"
version = "0.1.0"
edition = "2021"

[dependencies]
egui = "0.31"
egui_plot = { git = "https://github.com/emilk/egui_plot", branch = "main" }
eframe = { version = "0.31", default-features = false, features = ["x11", "default_fonts", "wgpu"] }
```

**Expected behavior**

The x axis for both the cursor and the plot should be linked even while auto bounds is active.

**Screenshots**


As can be seen in the image both cursor and plot axis are not aligned properly.