Add releases badge to README

Author: binarymist

README.md

@@ -13,6 +13,10 @@ lambda functions of <a href="https://purpleteam-labs.com/" title="purpleteam"><e
   <img src="https://img.shields.io/badge/-documentation-blueviolet" alt="documentation">
 </a>
 
+<a href="https://github.com/purpleteam-labs/purpleteam-lambda/releases" title="latest release">
+  <img src="https://img.shields.io/github/v/release/purpleteam-labs/purpleteam-lambda?color=%23794fb8&include_prereleases" alt="GitHub release (latest SemVer including pre-releases)">
+</a>
+
 <!--<table>
   <tbody>
     <tr>