Bugfix S3 offsite backups
Bugfix S3 offsite backups

The keys were missing curly braces which caused the backup script to
incorrectly export the required values:

export
AWS_ACCESS_KEY_ID='%hiera('backup::offsite::job::aws_access_key_id')'
export
AWS_SECRET_ACCESS_KEY='%hiera('backup::offsite::job::aws_secret_access_key')'

alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet