NIFI-7143: Upgrade GCP dependency

[turcsanyip]

https://issues.apache.org/jira/browse/NIFI-7143

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[pvillard31]

I believe we also need to upgrade google-auth-library-oauth2-http to 0.20.0 in nifi-gcp-services-api/pom.xml - I recall an upgrade in the past where we missed this part and it caused issues because we included 2 different versions of the same dependency.

[turcsanyip]

@pvillard31 Thanks for the heads-up.
I updated google-auth-library-oauth2-http in the services-api-nar to the same version as in the processors-nar which is 0.18.0.
Please note that the latest google-cloud-bom version (0.122.2-alpha) leads to a build error in NiFi (details in NIFI-7143). That's why I upgraded to a recent (0.120.2-alpha), but not the latest version.

[pvillard31]

Closing manually... I didn't correctly change the commit message... It's merged to master, thanks @turcsanyip