fix: use regex end of string

Author: petergoes

static/.htaccess

@@ -8,6 +8,7 @@ Redirect 301 "/componenten/definition-of-done" "/handboek/component-bijdragen/de
 Redirect 301 "/counter-badge" "/number-badge"
 Redirect 301 "/definition-list" "/description-list"
 Redirect 301 "/handboek/designer/community" "/community"
+Redirect 301 "/handboek/designer$" "/handboek/designer/introductie"
 Redirect 301 "/handboek/designer/nieuwe-versie-publiceren" "/handboek/designer/werken-met-nl-design-system"
 Redirect 301 "/handboek/designer/nieuwe-versie-publiceren/versiebeheer-voor-design-tokens" "/handboek/designer/design-tokens-versiebeheer"
 Redirect 301 "/handboek/designer/nieuwe-versie-publiceren/werken-met-changelog-voor-figma" "/handboek/designer/werken-met-figma-changelog"