doc: fix spacing issue in --build-snapshot help text

PR-URL: nodejs/node#44435
Reviewed-By: Anna Henningsen <[email protected]>
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: Tobias Nießen <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>
Reviewed-By: Kohei Ueno <[email protected]>
Reviewed-By: Rich Trott <[email protected]>
Reviewed-By: LiviaMedeiros <[email protected]>
Reviewed-By: Antoine du Hamel <[email protected]>

Author: syohex

src/node_options.cc

@@ -750,7 +750,7 @@ PerProcessOptionsParser::PerProcessOptionsParser(
             kAllowedInEnvironment);
   AddOption("--build-snapshot",
             "Generate a snapshot blob when the process exits."
-            "Currently only supported in the node_mksnapshot binary.",
+            " Currently only supported in the node_mksnapshot binary.",
             &PerProcessOptions::build_snapshot,
             kDisallowedInEnvironment);