Grab this value once at the top of the file into a variable, something like:
```
var configuredSiteLocation = process.env.AZURE_SITE_TEST_LOCATION;

 
cmd.push(configuredSiteLocation || 'East US');
```

This way if the environment variable changes, or we change how we get the default, it only changes in one spot.

Same comment for the other similar usages below.