fix: prevent jobPb.getConfiguration() to throw a NPE

[AzemaBaptiste]

Fixes #186 ☕️

An NullPointerException is throw when we run a bigquery.listJobs() with a service account using the permission bigquery.jobs.list. If the permission is set to bigquery.jobs.listAll, no NPE is thrown.

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[AzemaBaptiste]

Hello @prash-mi, I see you are marked as an reviewer for this PR.
I will be glad if you can have a look, this bug is pretty annoying.
Thanks!

[conventional-commit-lint-gcf]

🤖 I detect that the PR title and the commit message differ and there's only one commit. To use the PR title for the commit history, you can use Github's automerge feature with squashing, or use automerge label. Good luck human!

-- conventional-commit-lint bot
https://conventionalcommits.org/

[prash-mi]

Running the presubmits

[AzemaBaptiste]

Up @prash-mi is there something blocking here ?