Need dryrun support in the rvmc container

[Eric MacDonald]

Brief Description
-----------------
The Redfish Virtual Media Controller (RVMC) executes a series of query operations followed by the actual actions that send commands to the BMC.

The actions perform an installation of a server from an ISO loaded into that server's virtual media CD/DVD.

This issue calls for the RVMC to support a 'dryrun' mode that would perform the query but avoid the actions. This way, before actually performing the install it is possible to verify the BMC is ping-able, that a login session can be created with the supplied login credentials, the redfish tree is responsive and readable and confirm communication is with the expected target server.

Severity
--------
Minor: Debug tool

Steps to Reproduce
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run rvmc

Expected Behavior
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Ability to run the rvmc without taking actions.

Actual Behavior
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all query and action are taken whenever the rvmc is invoked.

Reproducibility
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100% since requested feature is not currently implemented.

System Configuration
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Distributed Cloud

Branch/Pull Time/Commit
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time of issue creation

Last Pass
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N/A

Timestamp/Logs
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N/A

Test Activity
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Feature and Regression testing

Workaround
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Modify the code manually

[Ghada Khalil (gkhalil)]

screening: minor; tool enhancement