Fix link and clean up frontmatter in health (#9813)

health/QUICKSTART.md

@@ -1,9 +1,6 @@
 <!--
----
 title: "Health quickstart"
-date: 2020-04-27
 custom_edit_url: https://github.com/netdata/netdata/edit/master/health/QUICKSTART.md
----
 -->
 
 # Health quickstart

health/README.md

@@ -1,9 +1,6 @@
 <!--
----
 title: "Health monitoring"
-date: 2020-04-24
 custom_edit_url: https://github.com/netdata/netdata/edit/master/health/README.md
----
 -->
 
 # Health monitoring

health/REFERENCE.md

@@ -1,9 +1,6 @@
 <!--
----
 title: "Health configuration reference"
-date: 2020-04-27
-custom_edit_url: <https://github.com/netdata/netdata/edit/master/health/REFERENCE.md>
----
+custom_edit_url: https://github.com/netdata/netdata/edit/master/health/REFERENCE.md
 -->
 
 # Health configuration reference