Powershell statement requires quotes.
Powershell statement requires quotes.

Otherwise, powershell complains:
```ps1
/path/to/service_account_key.json : The term '/path/to/service_account_key.json' is not recognized as the name of a cmdlet, function, script file, or operable program.
Check the spelling of the name, or if a path was included, verify that the path is correct and try again.
```
GoogleCloudPlatform/kotlin-samples