fix(job-exec): support all volume options in job-exec module

[PFacheris]

Fixes #286. Not sure why these options aren't available in the job-exec module so just copied them over from the v2 module. Tested with a GCS volume and works perfectly.

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[pataquets]

@PFacheris : Are you still interested/available to move this forward? Are you OK with sb else picking it up?

[PFacheris]

@pataquets I'm fine with someone else picking it up though as far as I'm aware there's not really anything to be done at the moment. Just waiting on someone from the Google side to take a look and provide any feedback.

cc: @anamer @ayushmjain @prabhu34 or @q2w (since I see you listed as the code owners)

[q2w]

@PFacheris Could you run command for generating the documentation? https://codelabs.developers.google.com/cft-onboarding/#8

[PFacheris]

@PFacheris Could you run command for generating the documentation? https://codelabs.developers.google.com/cft-onboarding/#8

Apologies for the delay on this, done now! Let me know if there's anything else.