fix clang

Author: Samuel Facchinello

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

@@ -10,6 +10,9 @@ public class ColumnarTranspositionCipher {
 
     private static final char PADDING_CHAR = '≈';
 
+    private ColumnarTranspositionCipher() {
+    }
+
     /**
      * Encrypts a message using the Columnar Transposition Cipher with the given key.
      *

src/test/java/com/thealgorithms/ciphers/ColumnarTranspositionCipherTest.java

@@ -1,14 +1,13 @@
 package com.thealgorithms.ciphers;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
+
+import java.util.stream.Stream;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.Arguments;
 import org.junit.jupiter.params.provider.MethodSource;
 
-import java.util.stream.Stream;
-
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertNotEquals;
-
 class ColumnarTranspositionCipherTest {
 
     @ParameterizedTest