Corrected README.md

Author: Krounosity

README.md

@@ -425,7 +425,7 @@ In order to achieve greater coverage and encourage more people to contribute to
                 </a>
             </td>
             <td> <!-- Java -->
-                <a href="./src/java/SentinelLinearSearch.java.md">
+                <a href="./src/java/SentinelLinearSearch.java">
                     <img align="center" height="25" src="./logos/java.svg" />
                 </a>
             </td>