cli/command/volume: various fixes and improvements in tests

[thaJeztah]

cli/command/volume: TestVolumeCreateErrors: assert unhandled errors

cli/command/volume: TestVolumeCreateWithName: minor fixes and improvements

• assert unhandled error
• use sub-tests
• add test-case for conflicting options (both flag and name)
• reset command-args to prevent test failing when running from pre-compiled test-binary
• use a const and a slightly more unique name for the volume-name
• discard stdout/stderr output

cli/command/volume: TestVolumeCreateWithFlags: minor fixes

• assert unhandled error
• reset command-args to prevent test failing when running from pre-compiled test-binary
• use a const and a slightly more unique name for the volume-name
• discard stdout/stderr output

cli/command/volume: TestVolumeCreateCluster: minor fixes and refactor

• assert unhandled error
• use sub-tests
• use slightly more unique volume-names
• discard stdout/stderr output

cli/command/volume: TestVolumeCreateClusterOpts: minor fixes and refactor

• assert unhandled error
• discard stdout/stderr output

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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 59.42%. Comparing base (bdd70c1) to head (341e665).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #5782   +/-   ##
=======================================
  Coverage   59.42%   59.42%           
=======================================
  Files         347      347           
  Lines       29402    29402           
=======================================
  Hits        17472    17472           
  Misses      10958    10958           
  Partials      972      972