The gcloud SDK moved the location of its config file from ~/.config/gcloud/properties to ~/.config/gcloud/configurations/config_default. As a result, the file we read to get the default project ID in gcloud-java-core may be wrong, depending on whether the user updated their version of the gcloud SDK CLI.

We should first check if a config file exists in the new location. If so, we take that projectID. If it doesn't exist, we will try to read the old file.