Add readOnlyInputs option for CharliecloudBuilder

[l-modolo]

This merge request is to add the readOnlyInputs option as discussed in the Charliecloud and shared cacheDir #3367 issue and following the Add readOnlyInputs option for CharliecloudBuilder #3477 merge request

With this modification:

• the default readOnlyInputs value is false
• if readOnlyInputs is true;
• the -w option is removed from the command
• the bound volumes are transformed to only mount the first folder of the path

For example, if I try to bind /home/user/workdir/ to /home/ the bound path will be /home to /home. By doing that, charliecloud doesn't try to mkdir -p /home/user/workdir/ within the read-only container, the external path is bound at the /home directory level so all the subfolders are accessible with the user rights. If one tries to bind / I added an expection.

Signed-off-by: Laurent Modolo [email protected]

[pditommaso]

Included in version 23.02.0-edge