chore: use iwyu on machine_learning/**.cpp

machine_learning/adaline_learning.cpp

@@ -26,15 +26,14 @@
  * computed using stochastic gradient descent method.
  */
 
-#include <array>
-#include <cassert>
-#include <climits>
-#include <cmath>
-#include <cstdlib>
-#include <ctime>
-#include <iostream>
-#include <numeric>
-#include <vector>
+#include <bits/std_abs.h>  // for abs
+#include <array>           // for array
+#include <cassert>         // for assert
+#include <cstdlib>         // for rand, exit, srand, strtof, EXIT_FAILURE
+#include <ctime>           // for time
+#include <iostream>        // for basic_ostream, operator<<, char_traits, cout
+#include <numeric>         // for inner_product
+#include <vector>          // for vector
 
 /** Maximum number of iterations to learn */
 constexpr int MAX_ITER = 500;  // INT_MAX