Allow also only 1 subsecond for absolute positive URLs

This proves why extraction is needed.

Author: vmcj

webapp/src/Validator/Constraints/TimeStringValidator.php

@@ -26,7 +26,7 @@ public function validate(mixed $value, Constraint $constraint): void
 
         if ($constraint->allowRelative) {
             $regex   = $constraint->relativeIsPositive ?
-                "/^(\d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d(\.\d{2,6})? " . $timeZoneRegex . "|\+?" . $relativeRegex . ")$/" :
+                "/^(\d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d(\.\d{1,6})? " . $timeZoneRegex . "|\+?" . $relativeRegex . ")$/" :
                 "/^(\d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d(\.\d{1,6})? " . $timeZoneRegex . "|-"   . $relativeRegex . ")$/";
             $message = $constraint->absoluteRelativeMessage;
         } else {