doc: match console.count()/countReset() signatures

PR-URL: #20599
Reviewed-By: Vse Mozhet Byt <vsemozhetbyt@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

doc/api/console.md

@@ -164,7 +164,7 @@ operates similarly to the `clear` shell command. On Windows, `console.clear()`
 will clear only the output in the current terminal viewport for the Node.js
 binary.
 
-### console.count([label])
+### console.count([label='default'])
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