various: boldify version output

Follow-up for 4453ebe4db.
With the feature list all dandified, the most important part of the
output, i.e. the project name and version, are less visible.

src/basic/build.c

@@ -276,7 +276,8 @@ int version(void) {
         if (colors_enabled())
                 b = systemd_features_with_color();
 
-        printf("systemd " STRINGIFY(PROJECT_VERSION) " (" GIT_VERSION ")\n%s\n",
+        printf("%ssystemd " STRINGIFY(PROJECT_VERSION) "%s (" GIT_VERSION ")\n%s\n",
+               ansi_highlight(), ansi_normal(),
                b ?: systemd_features);
         return 0;
 }