style: include RV_RETURN_VALUE_IGNORED

Author: vil02

spotbugs-exclude.xml

@@ -107,9 +107,6 @@
     <Match>
         <Bug pattern="NP_IMMEDIATE_DEREFERENCE_OF_READLINE" />
     </Match>
-    <Match>
-        <Bug pattern="RV_RETURN_VALUE_IGNORED" />
-    </Match>
     <Match>
         <Bug pattern="EQ_COMPARETO_USE_OBJECT_EQUALS" />
     </Match>

src/main/java/com/thealgorithms/ciphers/HillCipher.java

@@ -144,7 +144,6 @@ public static int determinant(int[][] a, int n) {
 
     // Function to implement Hill Cipher
     static void hillCipher(String message) {
-        message.toUpperCase();
         System.out.println("What do you want to process from the message?");
         System.out.println("Press 1: To Encrypt");
         System.out.println("Press 2: To Decrypt");