Add slogan and description to M3O sponsor (#1932)

ref 1: https://github.com/public-apis/public-apis/issues/1932#issuecomment-1027413074
ref 2: https://github.com/public-apis/public-apis/issues/1932#issuecomment-1027617827

README.md

@@ -69,6 +69,12 @@
             <div>
                 <img src="https://raw.githubusercontent.com/public-apis/public-apis/master/.github/assets/sponsors_logo/m3o_logo_black.png" width="250" alt="M3O Logo" />
             </div>
+            <div>
+                <p><strong>The fastest way to integrate APIs into any product</strong></p>
+            </div>
+            <div>
+                <sup>Explore, discover and consume public APIs as simpler programmable building blocks all on one platform for a 10x developer experience.</sup>
+            </div>
         </a>
     </p>
 </div>