Docs: update / centralize OGC Compliance links (#2204)

Author: tomkralidis

docs/source/_templates/indexsidebar.html

@@ -4,19 +4,19 @@
         <a title="pygeoapi.io" href="https://pygeoapi.io"><img style="background: white;" title="pygeoapi logo" alt="pygeoapi logo" src="_static/pygeoapi-logo.png" height="63" /></a>
     </p>
 
-    <a title="Certified OGC Compliant" href="https://www.ogc.org/resource/products/details/?pid=1663">
+    <a title="Certified OGC Compliant" href="https://github.com/geopython/pygeoapi/wiki/OGCCompliance">
         <img alt="Certified OGC Compliant" src="https://portal.ogc.org/public_ogc/compliance/OGC_Certified_Badge.png" width="164" height="64"/>
     </a>
-    <a title="OGC Reference Implementation" href="https://www.ogc.org/resource/products/details/?pid=1663">
+    <a title="OGC Reference Implementation" href="https://github.com/geopython/pygeoapi/wiki/OGCCompliance">
         <img alt="OGC Reference Implementation" src="https://portal.ogc.org/public_ogc/compliance/badge.php?s=ogcapi-features-1%201.0&r=1&n=1))" width="164" height="44"/>
     </a>
-    <a title="OGC Reference Implementation" href="https://www.ogc.org/resource/products/details/?pid=1663">
+    <a title="OGC Reference Implementation" href="https://github.com/geopython/pygeoapi/wiki/OGCCompliance">
         <img alt="OGC Reference Implementation" src="https://portal.ogc.org/public_ogc/compliance/badge.php?s=ogcapi-edr-1%201.0.1&r=1&n=1)" width="164" height="44"/>
     </a>
-    <a title="OGC Reference Implementation" href="https://www.ogc.org/resource/products/details/?pid=1663">
+    <a title="OGC Reference Implementation" href="https://github.com/geopython/pygeoapi/wiki/OGCCompliance">
         <img alt="OGC Reference Implementation" src="https://portal.ogc.org/public_ogc/compliance/badge.php?s=ogcapi-tiles-1%201.0.1&r=1&n=1)" width="164" height="44"/>
     </a>
-    <a title="OGC Reference Implementation" href="https://www.ogc.org/resource/products/details/?pid=1826">
+    <a title="OGC Reference Implementation" href="https://github.com/geopython/pygeoapi/wiki/OGCCompliance">
         <img alt="OGC Reference Implementation" src="https://portal.ogc.org/public_ogc/compliance/badge.php?s=ogcapi-processes-1%201.0.1&n=1)" width="164" height="44"/>
     </a>
     <a title="OSGeo Project" href="https://www.osgeo.org/projects/pygeoapi">