Vault access denied should be an exception

[niclan]

Vault secrets being null or empty is an exception.

Access denied results in empty secrets and and therefore the principle of least surprise dictates that the failed secret fetching should fail the build - otherwise user ends up with a build with empty secrets.

Relevant tickets:

• https://github.com/jenkinsci/hashicorp-vault-plugin/issues/162
• https://github.com/jenkinsci/hashicorp-vault-plugin/issues/156

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• [x] Ensure you have provided tests - that demonstrates feature works or fixes the issue

[niclan]

I hope you find my trivial change to your liking.

Sorry, I don't know java so I'm a bit short on competence to write tests but I note that I managed to introduce no syntax errors :-)

The CI / Build on Jenkins 2.164.3, JDK 11 and ubuntu-latest build failure I'm similarly incompetent to solve, but it appears to be related to maven not my change.

[msinger-dev]

Hi @ash1425! I would like to pick up on this PR. We also thought that throwing an exception on Access Denied would be nice. Should I create a new Ticket for that? Do you think we could re-use the "Fail if path is not found" flag or create a separate one for Access Denied? CC @jetersen (maybe you can help us with how to proceed here, as you are the top contributor/reviewing a lot😃)

[niclan]

Better PR #257 . But this issue should be solved!