refactoring: use ggT function from previous instead of new one

src/kgV/kgV.c

@@ -1,18 +1,5 @@
 #include <stdio.h>
-
-int ggT(int a, int b){
-    // handles the zero cases
-    if(a == 0) return b;
-    if(b == 0) return a;
-
-    // Euclidean algorithm with modulo for getting the ggT
-    while (b != 0) {
-        int temp = b;
-        b = a % b;
-        a = temp;
-    }
-    return a;
-}
+#include "ggT.h"
 
 int kgV(int a, int b){
     return a*b/ ggT(a, b);