Update whitelist.htm

Remove dead link for greylist monitoring site

guides/whitelist.htm

@@ -31,7 +31,6 @@ <h5>Please note:</h5>
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                     <h3>Greylist</h3>
                     <p>When projects are running out of work or are offline for temporary maintenance they are placed on the Greylist.  These projects will not reward Gridcoin until they meet the requirements to be placed back on the whitelist again.  Please see various social media (Twitter, Facebook, Reddit, Slack) for notices about greylisted projects.</p>
-                    <p>Please see <a href="https://gridcoin.ddns.net/pages/project-list.php">this unofficial Gridcoin Greylist monitoring website</a> for daily updates on which projects are added and removed from the Greylist. </p>
                     <p>The <a href="/wiki/whitelist-process.html#greylist">whitelist process wiki page</a> outlines the Greylist procedure for all whitelisted projects.</p>
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