update lang placeholder

Author: jcayouette

Makefile.j2

@@ -41,6 +41,7 @@ prepare-antora-suma-{{ langcode }}: copy-branding-{{ langcode }} set-html-langua
 	s/\-\ url\:\ \./\-\ url\:\ \.\.\/\.\.\//;\
 	s/start_path\:\ \./\start_path\:\ translations\/{{ langcode }}/;\
 	s/dir:\ \.\/build\/en/dir:\ \.\.\/\.\.\/build\/{{ langcode }}/;" site.yml > translations/{{ langcode }}/suma-site.yml && \
+	find translations/{{ langcode }}/branding/supplemental-ui -name "*.hbs" -exec sed -i 's/LANG_PLACEHOLDER/{{ langcode }}/g' {} \; && \
 	cp -a $(current_dir)/modules $(current_dir)/translations/en/
 	find modules/ -maxdepth 1 -name "*" -type d -exec mkdir -p $(current_dir)/translations/{{ langcode }}/{} \; && \
 	mkdir -p $(current_dir)/translations/{{ langcode }}/modules/ROOT/pages/