docs: fix LAB extrema documentation

Fix: 343778621
Flag: N/A
Test: manual using go/BeeShell:

bsh> com.android.internal.graphics.ColorUtils.colorToLAB(android.graphics.Color.WHITE, lab);
$19 = null
bsh> Arrays.toString(lab)
$20 = "[100.0, 0.00526049995830391, -0.010408184525267927]"

bsh> xyz = new double[3];
$22 = [D@fbe51c5
bsh> com.android.internal.graphics.ColorUtils.RGBToXYZ(255, 255, 255, xyz);
$23 = null
bsh> Arrays.toString(xyz)
$24 = "[95.05, 100.0, 108.89999999999999]"
bsh> com.android.internal.graphics.ColorUtils.XYZToLAB(xyz[0], xyz[1], xyz[2], lab);
$25 = null
bsh> Arrays.toString(lab)
$26 = "[100.0, 0.00526049995830391, -0.010408184525267927]"

Change-Id: I83ccf289578ac66d901d884433909e1b99b4ab40