ACP2E-345: Unable to save product URL key with a hyphen "-" at end.

- Updated validation error message to be more clear for user
- Updated MFTF test accordingly

Author: Mohan Ahuja

app/code/Magento/Catalog/Test/Mftf/Test/AdminCreateSimpleProductTest/AdminCreateSimpleProductUrlKeyTest.xml

@@ -29,16 +29,16 @@
 
         <fillField stepKey="fillUrlKey1" selector="{{AdminProductFormBundleSection.urlKey}}" userInput="example-page-"/>
         <click stepKey="blurFromUrlKey1" selector="{{AdminProductSEOSection.metaTitleInput}}"/>
-        <see selector="{{AdminProductFormSection.fieldError('url_key')}}" userInput="Please enter a valid URL Key (Ex: example-page)." stepKey="seeLastHyphenErrorMessage"/>
+        <see selector="{{AdminProductFormSection.fieldError('url_key')}}" userInput="Trailing hyphens are not allowed." stepKey="seeLastHyphenErrorMessage"/>
 
         <clearField selector="{{AdminProductFormBundleSection.urlKey}}" stepKey="clearFieldUrlKey2"/>
         <fillField stepKey="fillUrlKey2" selector="{{AdminProductFormBundleSection.urlKey}}" userInput="-Example-Page"/>
         <click stepKey="blurFromUrlKey2" selector="{{AdminProductSEOSection.metaTitleInput}}"/>
-        <see selector="{{AdminProductFormSection.fieldError('url_key')}}" userInput="Please enter a valid URL Key (Ex: example-page)." stepKey="seeFirstHyphenErrorMessage"/>
+        <see selector="{{AdminProductFormSection.fieldError('url_key')}}" userInput="Trailing hyphens are not allowed." stepKey="seeFirstHyphenErrorMessage"/>
 
         <clearField selector="{{AdminProductFormBundleSection.urlKey}}" stepKey="clearFieldUrlKey3"/>
         <click stepKey="blurFromUrlKey3" selector="{{AdminProductSEOSection.metaTitleInput}}"/>
         <fillField stepKey="fillUrlKey3" selector="{{AdminProductFormBundleSection.urlKey}}" userInput="example-page-test"/>
-        <dontSee selector="{{AdminProductFormSection.fieldError('url_key')}}" userInput="Please enter a valid URL Key (Ex: example-page)." stepKey="dontSeeErrorMessage"/>
+        <dontSee selector="{{AdminProductFormSection.fieldError('url_key')}}" userInput="Trailing hyphens are not allowed." stepKey="dontSeeErrorMessage"/>
     </test>
 </tests>

app/code/Magento/Ui/view/base/web/js/lib/validation/rules.js

@@ -821,7 +821,7 @@ define([
             function (value) {
                 return utils.isEmptyNoTrim(value) || /^(?!-)(?!.*-$).+$/.test(value);
             },
-            $.mage.__('Please enter a valid URL Key (Ex: example-page).')
+            $.mage.__('Trailing hyphens are not allowed.')
         ],
         'validate-zip-international': [