feature: multipleselect fix
Fix:
- multipleselect: missing optionValue, optionLabel, placeholder
- checkboxes to use the same mixins as multicheckbox
Before:
After:
<solid-form-search
fields="categories"
widget-categories="solid-form-multipleselect-autocompletion-placeholder"
range-categories="https://api.regenerative.org.au/webhook/regen/produce_categories"
option-label-categories="ofn:label"
search-placeholder-categories="Product category"
search-text-categories="Product category"
placeholder-categories="Product category"
></solid-form-search>