CSR-1479 fix regex that prevents using number "1" as the...

first number in telephone number.

src/digital-components/phonenumber-question/phonenumber-question.vue

@@ -75,8 +75,13 @@ export default {
             // Update the phone number with the formatted version
             return formattedNumber;
         },
-        filterNumber() {
-            this.selectedValue = this.selectedValue.replace(/1/g, "");
+        filterNumber(event) {
+            const regex = /^(?!1)\d+/;
+            const inputValue = event.target.value;
+            if (!regex.test(inputValue)) {
+                // If the input violates the regex pattern, remove the leading 1
+                event.target.value = inputValue.replace(/^1/, "");
+            }
         },
     },
     watch: {