[BUG]: last period label sometimes not drawn when using negative ticklabelindex

Here is an example of the last ticklabel not being drawn. The figure's ticklabelindex is set to -1:

Plotly 3.6.0 (missing last label)

Plotly 3.5.1 (all labels visible)

This is a regression from #7735. In version 3.5.1 ticklabelindex was ignored because no minor ticks were drawn. In version 3.6.0 ticklabelindex is not ignored and so for this figure, the label is expected to be drawn to the left of each major tick (ticklabelindex -1). However, there is no tick to the right of the last period and so that period is not labeled.

Before ticklabelindex, period labels were only ever drawn to the right of a major tick. There is logic in plotly to add a helper tick before the first period, making sure it will be labeled. For negative ticklabelindex, the same logic is required for the period at the end of the axis range.

Codepen: https://codepen.io/toffi-fee/pen/MYJEWLY

リンクされた CodePen を使って不足しているラベルを再現し、3.5.1 と 3.6.0 の動作を比較します。ticklabelindex の処理と最初の期間に対する既存の helper-tick ロジックを追跡し、そのうえで、インデックスが負の場合に、範囲の終端における同等のケースで最後の期間にラベルが付くことを確認します。