Fix issue #3408

Remove including core.h or base.h

Author: gabime

include/spdlog/fmt/fmt.h

@@ -20,11 +20,7 @@
     #ifndef FMT_USE_WINDOWS_H
         #define FMT_USE_WINDOWS_H 0
     #endif
-
-    #include <spdlog/fmt/bundled/base.h>
     #include <spdlog/fmt/bundled/format.h>
-
 #else  // SPDLOG_FMT_EXTERNAL is defined - use external fmtlib
-    #include <fmt/base.h>
     #include <fmt/format.h>
 #endif