bug #39341 [Form] Fixed StringUtil::trim() to trim ZERO WIDTH SPACE (U+200B) and SOFT HYPHEN (U+00AD) (pmishev)

This PR was merged into the 4.4 branch.

Discussion
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[Form] Fixed StringUtil::trim() to trim ZERO WIDTH SPACE (U+200B) and SOFT HYPHEN (U+00AD)

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | yes
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tickets       | Fix #39230 <!-- prefix each issue number with "Fix #", no need to create an issue if none exist, explain below instead -->
| License       | MIT
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Commits
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258bea7fd5 [Form] Fixed StringUtil::trim() to trim ZERO WIDTH SPACE (U+200B) and SOFT HYPHEN (U+00AD)

Author: derrabus

Tests/Util/StringUtilTest.php

@@ -72,7 +72,9 @@ public function spaceProvider()
             ['000D'],
             ['0085'],
             // zero width space
-//            ['200B'],
+            ['200B'],
+            // soft hyphen
+            ['00AD'],
         ];
     }
 

Util/StringUtil.php

@@ -33,7 +33,7 @@ private function __construct()
      */
     public static function trim($string)
     {
-        if (null !== $result = @preg_replace('/^[\pZ\p{Cc}]+|[\pZ\p{Cc}]+$/u', '', $string)) {
+        if (null !== $result = @preg_replace('/^[\pZ\pC]+|[\pZ\pC]+$/u', '', $string)) {
             return $result;
         }