Adjust 睾 (U+777E) for JP and CN; separate issues for aforementioned locales

First topmost stroke before should be more consistent between CN and JP, prefer to centralize it to match JP balance (circled in orange). This is similar to the placement of the first stroke in 血 and 衆 (for example), across JP, KR and CN, it's standardized.

As for the 幸 part (circled in red), a new JP glyph would be needed for Serif. More details [here](https://github.com/adobe-fonts/source-han-serif/issues/176).