fix: fix build issues

num4j/src/main/java/com/onixbyte/nums/PercentileCalculator.java

@@ -33,7 +33,6 @@ import java.util.List;
  * <p>
  * This class is final, meaning it cannot be subclassed, and it only contains static methods,
  * so instances of the class cannot be created.
- * </p>
  * <h2>Example usage:</h2>
  * <pre>
  * {@code
@@ -49,6 +48,12 @@ import java.util.List;
  */
 public final class PercentileCalculator {
 
+    /**
+     * Private constructor prevents from being initialised.
+     */
+    private PercentileCalculator() {
+    }
+
     /**
      * Calculates the specified percentile from a list of values.
      * <p>

num4j/src/main/java/com/onixbyte/nums/model/QuartileBounds.java

@@ -29,7 +29,6 @@ package com.onixbyte.nums.model;
  *   <li>{@code lowerBound} - The lower bound of the dataset, typically {@code Q1 - 1.5 * IQR}.</li>
  *   <li>{@code upperBound} - The upper bound of the dataset, typically {@code Q3 + 1.5 * IQR}.</li>
  * </ul>
- * </p>
  * <p>
  * Example usage:
  * <pre>