Fix typo in example poster subtitle

Change-Id: I0d8930f41e5b2bc276d65c9bce4fb48c43a56b36
diff --git a/inst/rmarkdown/templates/posterdown_ids/skeleton/skeleton.Rmd b/inst/rmarkdown/templates/posterdown_ids/skeleton/skeleton.Rmd
index 6cf6da1..2f88dae 100644
--- a/inst/rmarkdown/templates/posterdown_ids/skeleton/skeleton.Rmd
+++ b/inst/rmarkdown/templates/posterdown_ids/skeleton/skeleton.Rmd
@@ -1,6 +1,6 @@
 ---
 title: Generate Reproducible IDS-CD compliant HTML and PDF Posters
-subtitle: Using RMarkdown and `posterdown::ids_poster`
+subtitle: Using RMarkdown and `posterdown::posterdown_ids`
 author:
   - name: Brent Thorne
     affil: 1