Add distance between two points algorithm (#7218)

* Add distance between two points algorithm

* Create DistanceBetweenTwoPointsTest.java

* DistanceBetweenTwoPoints.java

* Fix test file package and project structure

* Delete src/test/java/com/thealgorithms/DistanceBetweenTwoPointsTest.java

* Apply clang-format compliant formatting

* Apply clang-format

---------

Co-authored-by: a <19151554+alxkm@users.noreply.github.com>

src/test/java/com/thealgorithms/maths/DistanceBetweenTwoPointsTest.java

@@ -0,0 +1,23 @@
+package com.thealgorithms.maths;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+class DistanceBetweenTwoPointsTest {
+
+    @Test
+    void testDistanceSimple() {
+        assertEquals(5.0, DistanceBetweenTwoPoints.calculate(0, 0, 3, 4), 1e-9);
+    }
+
+    @Test
+    void testDistanceNegativeCoordinates() {
+        assertEquals(5.0, DistanceBetweenTwoPoints.calculate(-1, -1, 2, 3), 1e-9);
+    }
+
+    @Test
+    void testSamePoint() {
+        assertEquals(0.0, DistanceBetweenTwoPoints.calculate(2, 2, 2, 2), 1e-9);
+    }
+}