WX-1820 Google Cloud Batch Backend VPC configuration attribute fix

[dspeck1]

Description

Change in Google Cloud Batch Backend VPC configuration attributes to remove trailing slash in network subnet address. Google Cloud Backend no longer supports a trailing slash in the URL.

Release Notes Confirmation

CHANGELOG.md

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Terra Release Notes

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[mcovarr]

The GcpBatchVpcAndSubnetworkProjectLabelValuesSpec unit test is failing as a result of these changes.