cli: clarify --cpu-prof-name allowed values

Refs: #57418
PR-URL: #57433
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Yagiz Nizipli <[email protected]>

Author: cecia234

doc/api/cli.md

@@ -501,6 +501,15 @@ $ ls *.cpuprofile
 CPU.20190409.202950.15293.0.0.cpuprofile
 ```
 
+If `--cpu-prof-name` is specified, the provided value will be used as-is; patterns such as
+`${hhmmss}` or `${pid}` are not supported.
+
+```console
+$ node --cpu-prof --cpu-prof-name 'CPU.${pid}.cpuprofile' index.js
+$ ls *.cpuprofile
+'CPU.${pid}.cpuprofile'
+```
+
 ### `--cpu-prof-dir`
 
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