refactor: update validation and make it fail-fast

[aramase]

Signed-off-by: Anish Ramasekar anish.ramasekar@gmail.com

Reason for Change:

• Move validation a step before when deserializing the config from secret provider class
  • This helps avoid making additional key vault calls when there are errors in user-defined properties

Requirements

• squashed commits
• included documentation
• added unit tests and e2e tests (if applicable).

Issue Fixed:

Does this change contain code from or inspired by another project?

• Yes
• No

If "Yes," did you notify that project's maintainers and provide attribution?

Special Notes for Reviewers:

[codecov-commenter]

Codecov Report

Merging #917 (d68f4bd) into master (d90847c) will increase coverage by 0.76%.
The diff coverage is 79.22%.

@@            Coverage Diff             @@
##           master     #917      +/-   ##
==========================================
+ Coverage   61.39%   62.15%   +0.76%     
==========================================
  Files           8        9       +1     
  Lines         904      909       +5     
==========================================
+ Hits          555      565      +10     
+ Misses        314      311       -3     
+ Partials       35       33       -2     

[aramase]

/azp run pr-e2e-azure

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[aramase]

pr-e2e-azure results: https://dev.azure.com/AzureContainerUpstream/Secrets%20Store%20CSI%20Driver%20Provider%20Azure/_build/results?buildId=47189&view=results