fix: missing footer in landing

Author: sgratzl

content/covidcast/overview.md

@@ -7,5 +7,4 @@ app_mode: overview
 order: 3
 heroImage: /images/landing-page/hero-images/covidcast_withfill.jpg
 feedback: true
-footer: true
 ---

themes/delphi/layouts/_default/covidcast_app.html

@@ -6,7 +6,7 @@
   <script src="{{ (partial "covidcast/find-file.html" "bundle.*\\.js$")| relURL }}"></script>
 {{ end }}
 {{ define "breadcrumb" }}<!-- no breadcrumb -->{{ end }}
-{{ define "body_class" }}covidcast_wrapper {{ if .Params.footer }}covidcast_wrapper_footer{{ end }}{{ end }}
+{{ define "body_class" }}covidcast_wrapper {{ if ne .Params.footer false }}covidcast_wrapper_footer{{ end }}{{ end }}
 {{ define "main" }}
   <div id="vizbox">
     <div class="ie-banner" style="display: none">