This commit fixes a minor error in the sed commands used to prefix
namespaces in the vendor folder. Due to an extra space sed was
considering `.bak` an extra parameter. If we use `-i.bak` instead (without the
space), sed creates a backup file which is the desired behavior.
With this change we won't be getting the errors below when running
`composer install` or `composer update`:
```
Generating autoload files
> sh ./bin/prefix-vendor-namespaces.sh
Prefixing the appropriate vendor namespaces with Automattic\WooCommerce\Vendor
sed: can't read .bak: No such file or directory
sed: can't read .bak: No such file or directory
sed: can't read .bak: No such file or directory
(...)
```
Since sed was working without creating a backup file, I wonder if we
really need to create one. I tested and `sed -i -E -e
"s/\"(League\\\\\\\Container)/\"Automattic\\\\\\\WooCommerce\\\\\\\Vendor\\\\\\\\\1/g"
vendor/league/container/composer.json` works well in Linux. If it also
works on Mac, maybe we can use it and remove the code that deletes the
.bak files?
All the classes in the package are re-namespaced from
"Leage\Container" to "Automattic\WooCommerce\Vendor\League\Container"
to prevent conflicts with extensions using the same plugin.
The re-namespacing is done by using a simple text substitution
on all the code files (see prefix-vendor-namespaces.sh), for this
particular case this approach is enough.