[BUG] GA is always enqueued, even without a valid tag

[jaymcp]

Describe the bug
Google Analytics support has a default option fallback of test here.
This means that the GTM script is always output, even if the user has no desire to use GA. Users would have to unhook the call to prevent the script from outputting.

To Reproduce
Steps to reproduce the behaviour:

1. Install & activate the theme.

Expected behaviour
When no GA code is added to the theme's options, no GTM script should be output.

Screenshots

Platform (please complete the following information):
Platform-independent. Affects all versions of Benenson.

[ampersarnie]

Annoying that ended up in there.