This function had the exacyt same behavior as the 'UI' operators, make
local invoqued on a linked liboverride would make the data local, but
would not clear the liboverride data from it. User then needs to call
this operation again if they want to remove that liboverride data.
The new `clear_liboverride` parameter to `ID.make_local` forces always
clearing any liboverride data, and allows to make a linked liboverride
fully local with a single call.
This option is kept disabled by default, to ensure default behavior
remains unchanged.
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