refactoring: free allocated memory in test functions

test/conversionOfNumbers/test_conversionOfNumbers.c

@@ -1,5 +1,6 @@
 #include "unity.h"
 #include "conversionOfNumbers.h"
+#include <stdlib.h>
 
 void setUp(){}
 void tearDown(){}
@@ -14,6 +15,7 @@ void test_convert2ToBinaryStr10(){
 
     //assert
     TEST_ASSERT_EQUAL_STRING(expected, result);
+    free(result);
 }
 
 void test_binaryStringLengthOfInput5is3(){
@@ -50,6 +52,7 @@ void test_convert10ToBinaryStr1010(){
 
     //assert
     TEST_ASSERT_EQUAL_STRING(expected, result);
+    free(result);
 }
 
 void test_binaryStringLengthOfInputNegative10is5(){
@@ -74,4 +77,5 @@ void test_convertNegative12ToBinaryStrNegative1100(){
 
     //assert
     TEST_ASSERT_EQUAL_STRING(expected, result);
+    free(result);
 }