fix(pivot-grid): do not use dataMapper for pivot row cell values - 19.2.x#16449

kacheshmarova merged 2 commits into19.2.xIgniteUI/igniteui-angular:19.2.xfrom

bpachilova/fix-pivot-cell-dataMapper-16445-19.2.xIgniteUI/igniteui-angular:bpachilova/fix-pivot-cell-dataMapper-16445-19.2.xCopy head branch name to clipboard