fix: IWYU

src/core/include/mp-units/bits/fmt.h

@@ -36,6 +36,7 @@
 
 #ifndef MP_UNITS_IN_MODULE_INTERFACE
 #include <gsl/gsl-lite.hpp>
+#include <array>
 #include <concepts>
 #include <cstdint>
 #include <limits>

test/static/fixed_string_test.cpp

@@ -21,6 +21,7 @@
 // SOFTWARE.
 
 #include <mp-units/ext/fixed_string.h>
+#include <array>
 #include <string_view>
 
 using namespace mp_units;