[typeahead-search] Make search button appear as part of input box
Applies a negative margin to .wvui-typeahead-search__wrapper and
.wvui-typeahead-search__submit causing the border of these elements to
intentionally overlap with the border applied to
- Moved &--has-value selector above the &--active selector due to
eslint complaining about descending specificity. Also removed unneeded
nesting in the former's selector.
- Removed unneeded/redundant styles in .wvui-input__input.
- Removed unneeded max-width style in &__suggestions
- Reordered several styles per Volker's suggestion.