Prepare for development of 0.21.2-SNAPSHOT (#43)

* Release 0.21.1

* Prepare for next development iteration 0.21.2-SNAPSHOT

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Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

Author: brianoliver

pom.xml

@@ -57,7 +57,7 @@
 
     <properties>
         <!-- Project and Module Versions -->
-        <revision>0.21.1-SNAPSHOT</revision>
+        <revision>0.21.2-SNAPSHOT</revision>
 
         <!-- Project Build Properties -->
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>