make check fails with "ERROR Namespace dependencies not required: ccdata, sdcMicro, yaml"

[tompollard]

Running make check (or R CMD check '.') raises the following error:

* checking package namespace information ... OK
* checking package dependencies ... ERROR
Namespace dependencies not required: ‘ccdata’ ‘sdcMicro’ ‘yaml’

See section ‘The DESCRIPTION file’ in the ‘Writing R Extensions’
manual.
* DONE

Status: 1 ERROR

It looks like this issue can be fixed by adding ccdata, sdcMicro, yaml to the imports field in the DESCRIPTION file, so the following entry:

Imports: data.table

...becomes

Imports: data.table, ccdata, sdcMicro, yaml