Updating saving file path for `sbf_backup_pg`

[aylapear]

• updated docs
• updating sbf_backup_pg() to auto create the saving path to be output instead of manually having to write out the file paths
• removed restrictive check in sbf_path_db() that conflicted the docs/parameter
• updated psql option from psql.value to psql.config_value to be more consistent with the other option name

[aylapear]

minor updates once package was used in production