🐛 add missing header to input_adapters.hpp (nlohmann#4830)

Signed-off-by: David Kilzer <ddkilzer@apple.com>
Co-authored-by: David Kilzer <ddkilzer@apple.com>

Author: ddkilzer

include/nlohmann/detail/input/input_adapters.hpp

@@ -14,6 +14,7 @@
 #include <iterator> // begin, end, iterator_traits, random_access_iterator_tag, distance, next
 #include <memory> // shared_ptr, make_shared, addressof
 #include <numeric> // accumulate
+#include <streambuf> // streambuf
 #include <string> // string, char_traits
 #include <type_traits> // enable_if, is_base_of, is_pointer, is_integral, remove_pointer
 #include <utility> // pair, declval

single_include/nlohmann/json.hpp

@@ -6503,6 +6503,7 @@ NLOHMANN_JSON_NAMESPACE_END
 #include <iterator> // begin, end, iterator_traits, random_access_iterator_tag, distance, next
 #include <memory> // shared_ptr, make_shared, addressof
 #include <numeric> // accumulate
+#include <streambuf> // streambuf
 #include <string> // string, char_traits
 #include <type_traits> // enable_if, is_base_of, is_pointer, is_integral, remove_pointer
 #include <utility> // pair, declval