DOCS: fix typo in markdown.md of template (#1421)

jupyter_book/book_template/markdown.md

@@ -78,7 +78,7 @@ You can also cite references that are stored in a `bibtex` file. For example,
 the following syntax: `` {cite}`holdgraf_evidence_2014` `` will render like
 this: {cite}`holdgraf_evidence_2014`.
 
-Moreoever, you can insert a bibliography into your page with this syntax:
+Moreover, you can insert a bibliography into your page with this syntax:
 The `{bibliography}` directive must be used for all the `{cite}` roles to
 render properly.
 For example, if the references for your book are stored in `references.bib`,