tools: fix typo in gen-postmortem-metadata.py

PR-URL: #17268
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Vse Mozhet Byt <vsemozhetbyt@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>

tools/gen-postmortem-metadata.py

@@ -3,7 +3,7 @@
 #
 # gen-postmortem-metadata.py output_file.cc
 #
-# Creates debugging symbols to help naviage Node's internals using post-mortem
+# Creates debugging symbols to help navigate Node's internals using post-mortem
 # debugging tools.
 #