Expose segmenter for countType: "words"

Unless the (deprecated) `maxwords` option is used

Author: colinrotherham

packages/govuk-frontend/src/govuk/components/character-count/character-count.mjs

@@ -131,7 +131,12 @@ export class CharacterCount extends ConfigurableComponent {
       locale: closestAttributeValue(this.$root, 'lang')
     })
 
-    if (this.config.countType === 'characters' || !!this.config.countFunction) {
+    if (
+      this.config.countType === 'characters' ||
+      (this.config.countType === 'words' &&
+        this.config.maxwords === undefined) ||
+      !!this.config.countFunction
+    ) {
       if (!('Segmenter' in Intl)) {
         throw new SupportError(
           formatErrorMessage(