Update README.md

Author: palemieux

README.md

@@ -9,6 +9,7 @@
                   /|                    |\                 
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+⚠️⚠️⚠️           CURRENTLY IN DEVELOPMENT          ⚠️⚠️⚠️
 
 ## Introduction
 
@@ -191,4 +192,4 @@ The operation of the `StreamingWriter` is demonstrated at
 
 - Java 17
 - Maven
-- (recommended) Git
+- (recommended) Git