one-context: growpart does not work if local is not english

The upstream bug is not yet closed as my pull request is not merged.

We should provide a work around or the volumes are not resized:

févr. 01 11:57:46 ubt one-contextd[813]: Script loc-05-grow-rootfs output: /usr/bin/growpart: 314: Illegal number: 53687091200 octets,
févr. 01 11:57:46 ubt one-contextd[813]:   Physical volume "/dev/sda4" changed
févr. 01 11:57:46 ubt one-contextd[813]:   1 physical volume(s) resized or updated / 0 physical volume(s) not resized
févr. 01 11:57:46 ubt one-contextd[813]:   New size (1327 extents) matches existing size (1327 extents).
févr. 01 11:57:46 ubt one-contextd[813]: resize2fs 1.45.5 (07-Jan-2020)
févr. 01 11:57:46 ubt one-contextd[813]: Le système de fichiers a déjà 1358848 blocs (4k). Rien à faire !