src: remove unused iomanip include

This commit removes the include of the IO manipulators header as I can't
find that it is used anywhere.

PR-URL: #30004
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

src/node_report.cc

@@ -18,7 +18,6 @@
 #include <ctime>
 #include <cwctype>
 #include <fstream>
-#include <iomanip>
 
 constexpr int NODE_REPORT_VERSION = 1;
 constexpr int NANOS_PER_SEC = 1000 * 1000 * 1000;