Change the focus behavior in MathCAT settings in NVDA

When going into MathCAT settings in NVDA, the focus is immediately inside the setting and not in the tabs of the settings like in core NVDA settings.

After moving focus into the tabs and moving with the arrow keys, the focus is moved to the inside the tab that was just navigated into. It should be possible to first move through all the tabs with the arrow keys and then move into the setting that you want to change.

從 NVDA 外掛程式中的 MathCAT 設定入口開始，將其索引標籤焦點處理與 NVDA 核心設定進行比較。完成標準是：焦點最初位於索引標籤清單上，方向鍵可以在索引標籤之間移動而不會進入其控制項，並且只有在執行明確的導覽後，焦點才會進入某個索引標籤的設定。

由索引模型根據 Issue 內容生成。