Signer TextBlock's vertical position misaligned in commit signature tooltip on Win10

[gadfly3173]

The Signer value in the commit signature tooltip is positioned higher than other labels and values in the grid layout.
Setting Height="16" for all elements works, but I'm not sure if it's the right approach

[gadfly3173]

This seems only happen on my Windows 10, my Deepin V23 could not reproduce this.

[gadfly3173]

VerticalAlignment并没有解决这个问题，我看下来感觉是windows上的换行符导致这里多了个换行

[love-linger]

我提交一版修复。这里不能直接使用 string.Split(['\n', '\r'], StringSplitOptions.RemoveEmptyEntries)，因为 Signer 可能为空。比如：