src: fix compiler warning in inspector_profiler.cc

Currently, the following compiler warnings is generated:

../src/inspector_profiler.cc:231:5: warning:
ignoring return value of function declared with 'warn_unused_result'
attribute [-Wunused-result]
profile->Set(context, FIXED_ONE_BYTE_STRING(isolate, "source-map-cache")
^~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 warning generated.

This commit adds a .ToChecked() call to avoid the warning.

PR-URL: #29660
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Minwoo Jung <minwoo@nodesource.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: danbev

src/inspector_profiler.cc

@@ -229,7 +229,7 @@ void V8CoverageConnection::WriteProfile(Local<String> message) {
   // Avoid writing to disk if no source-map data:
   if (!source_map_cache_v->IsUndefined()) {
     profile->Set(context, FIXED_ONE_BYTE_STRING(isolate, "source-map-cache"),
-                source_map_cache_v);
+                source_map_cache_v).ToChecked();
   }
 
   Local<String> result_s;