verticalAlignment property
The vertical alignment of the value in the cell. Possible string values are:
- "VERTICAL_ALIGN_UNSPECIFIED" : The vertical alignment is not specified. Do not use this.
 - "TOP" : The text is explicitly aligned to the top of the cell.
 - "MIDDLE" : The text is explicitly aligned to the middle of the cell.
 - "BOTTOM" : The text is explicitly aligned to the bottom of the cell.
 
Implementation
core.String? verticalAlignment;