[CredManUi] Updated paddings within an entry.

The horizontal elements padding should be 16dp. However, didn't realize
that the SuggestionChip element by default applies 8dp elements paddind
horizontally already. Hence we should only apply 8dp horizontal padding
ourselves.

Bug: 271168052
Test: manual (see bug for screenshot)
Change-Id: I5959a4a113df13e6e1eabb560d17a3745b40b42f