[ProductVariant] explanation note about minimum price in product vari…

…ant creation form

src/Sylius/Bundle/AdminBundle/Resources/translations/messages.en.yml

@@ -51,7 +51,8 @@ sylius:
         product:
             product_not_active_in_channel: The product is not yet activated in this channel.
         original_price_details: Original price - this is the price of the product variant It is displayed as crossed-out in the catalog. It is used as the base for current price calculations. If this value is not definded, Catalog Promotion logic will copy value from Price to Original Price. 
-        price_details: Price - this is the current price of the product variant displayed in the catalog. It can be modified explicitly by i.e. catalog promotions. 
+        price_details: Price - this is the current price of the product variant displayed in the catalog. It can be modified explicitly by i.e. catalog promotions.
+        minimum_price_details: Minimum price - this is the pricing threshold below which the current price cannot be discounted by neither catalog nor cart promotions. Use this to guard the profitability of your sales.
         gateway:
             no_sca_support_notice: The chosen payment gateway does not support SCA.
             pay_pal_express_checkout_deprecation_notice: >

src/Sylius/Bundle/AdminBundle/Resources/views/ProductVariant/Tab/_channelPricings.html.twig

@@ -4,6 +4,8 @@
         {{ 'sylius.ui.price_details'|trans }}
         <br/>
         {{ 'sylius.ui.original_price_details'|trans }}
+        <br/>
+        {{ 'sylius.ui.minimum_price_details'|trans }}
     </div>
     <div id="sylius_product_variant_channelPricings">
         {{ form_errors(form.channelPricings) }}