Update LOCAL_DEV_ENV.md (#489)

Use placeholder. **BYPASS_SECRET_SCANNING**

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Fixes
[AB#496928](https://dynamicssmb2.visualstudio.com/1fcb79e7-ab07-432a-a3c6-6cf5a88ba4a5/_workitems/edit/496928)

LOCAL_DEV_ENV.md

@@ -18,5 +18,5 @@ For instance, running the following will
 1. Publish the built apps and their dependencies to _BC-SystemApp_.
 
 ```
-.\build\scripts\DevEnv\NewDevEnv.ps1 -containerName 'BC-SystemApp' -userName admin -password 'MyP@ss' -projectPaths '.\src\System Application\*'
-```
+.\build\scripts\DevEnv\NewDevEnv.ps1 -containerName 'BC-SystemApp' -userName admin -password '<some password>' -projectPaths '.\src\System Application\*'
+```