fix(table): inherit vertical align in table footer

The default vertical alignment of table footer were explicitly set
as middle, which ignores the `top aligned` and `bottom aligned`
variant from table row and unable to align top and bottom within
table footer.

By setting default value as inherit will enable to specify vertical
alignment from table row without needing to specify on each cell.

src/themes/default/collections/table.variables

@@ -58,7 +58,7 @@
 @footerDivider: none;
 @footerBackground: @offWhite;
 @footerAlign: inherit;
-@footerVerticalAlign: middle;
+@footerVerticalAlign: inherit;
 @footerColor: @textColor;
 @footerVerticalPadding: @cellVerticalPadding;
 @footerHorizontalPadding: @cellHorizontalPadding;