from CRAN: don't write to user library

[sckott]

These all show check problems on the Debian check systems caused by
attempts to write to the user library to which all packages get
installed before checking (and which now is remounted read-only for
checking).

Having package code which is run as part of the checks and attempts to
write to the user library violates the CRAN Policy's

Packages should not write in the user’s home filespace (including
clipboards), nor anywhere else on the file system apart from the R
session’s temporary directory (or during installation in the location
pointed to by TMPDIR: and such usage should be cleaned up).

Hence, please update your package(s) as quickly as possible to no longer
(attempt to) write to the user library (including, of course, the
location where the package itself was installed to).