Fix PackageManagement tests (#733)
Fix PackageManagement tests (#733)

Ensure we load the configs before using them to create the client.


GoogleCloudPlatform/compute-image-tools,adjackura/compute-image-tools,GoogleCloudPlatform/compute-daisy,zmarano/compute-image-tools,GoogleCloudPlatform/compute-image-import,zmarano/compute-image-tools,GoogleCloudPlatform/compute-image-import,GoogleCloudPlatform/compute-image-tools,zmarano/compute-image-tools,adjackura/compute-image-tools,adjackura/compute-image-tools,GoogleCloudPlatform/compute-daisy,GoogleCloudPlatform/compute-image-import,GoogleCloudPlatform/compute-image-tools