add Anghel Leonard's github profile link

Author: dbc2201

.idea/sonarlint/issuestore/e/d/ed67eb178d523a4b3f117dcbe0eda5196367ceec

@@ -28,7 +28,8 @@ Write a program that counts duplicate characters from a given `String`.
 
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 > Question taken from the book
-> ["Java Coding Problems"](https://www.packtpub.com/product/java-coding-problems/9781789801415) by Anghel Leonard.  
+> ["Java Coding Problems"](https://www.packtpub.com/product/java-coding-problems/9781789801415) by
+> [Anghel Leonard](https://github.com/AnghelLeonard).  
 > Formatted and uploaded by [dbc2201](https://github.com/dbc2201)
 
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