Remove stale Cumulus blog links (#97)

* Remove stale Cumulus blog links

Author: ratulm

_includes/community-resources.html

@@ -129,17 +129,6 @@ <h5 class="mt-0">
                     <p>Rick Donato (@rickjdon)</p>
                 </div>
 
-                <div class="content-row my-4">
-                    <h4>Exploring Batfish with Cumulus</h4>
-                    <h5 class="mt-0">
-                        | <a href="https://cumulusnetworks.com/blog/exploring-batfish-with-cumulus-part-one/">Part 1: Getting started with Batfish and Cumulus</a>
-                    </h5>
-                    <h5 class="mt-0">
-                        | <a href="https://cumulusnetworks.com/blog/exploring-batfish-with-cumulus-part-2/">Part 2: Building a CI/CD pipeline with Batfish and Cumulus</a>
-                    </h5>
-                    <p>Anthony Miloslavsky (Cumulus, @permitanyany)</p>
-                </div>
-
                 <div class="content-row my-4">
                     <a href="https://eos.arista.com/network-ci-part-3/">
                             <h4>Building a network CI pipeline with Gitlab, Ansible, cEOS, Robot Framework and Batfish (Signup required)</h4>