[chore](build) Use include-what-you-use to optimize includes (PART II) (#18761)

Currently, there are some useless includes in the codebase. We can use a tool named include-what-you-use to optimize these includes. By using a strict include-what-you-use policy, we can get lots of benefits from it.

be/src/vec/functions/function_conv.cpp

@@ -15,14 +15,42 @@
 // specific language governing permissions and limitations
 // under the License.
 
+#include <stdint.h>
+#include <stdlib.h>
+
+#include <boost/iterator/iterator_facade.hpp>
+// IWYU pragma: no_include <bits/std_abs.h>
+#include <algorithm>
+#include <cmath> // IWYU pragma: keep
+#include <memory>
+#include <utility>
+
+#include "common/status.h"
 #include "exprs/math_functions.h"
+#include "util/string_parser.hpp"
+#include "vec/aggregate_functions/aggregate_function.h"
+#include "vec/columns/column.h"
 #include "vec/columns/column_const.h"
 #include "vec/columns/column_nullable.h"
+#include "vec/columns/column_string.h"
+#include "vec/columns/column_vector.h"
+#include "vec/columns/columns_number.h"
+#include "vec/common/assert_cast.h"
+#include "vec/common/string_ref.h"
+#include "vec/core/block.h"
+#include "vec/core/column_numbers.h"
+#include "vec/core/column_with_type_and_name.h"
 #include "vec/core/types.h"
+#include "vec/data_types/data_type.h"
+#include "vec/data_types/data_type_nullable.h"
 #include "vec/data_types/data_type_number.h"
 #include "vec/data_types/data_type_string.h"
+#include "vec/functions/function.h"
 #include "vec/functions/simple_function_factory.h"
-#include "vec/utils/util.hpp"
+
+namespace doris {
+class FunctionContext;
+} // namespace doris
 
 namespace doris::vectorized {