feat: changed minimum of 2 locales to minimum of 1

[dfdez]

Summary
I made these PR in order to be able to have only one locale, to cover some use cases in which we want to just have one.

Right now the only workaround is to just set i18n: false but this will change how the file / folder structure is generated

closes #6263

Test plan

The only modification that I made is to set the minItems property of locales property from 2 to 1.

Also I added a test for check that fails when locales are less than 1 (Previously there wasn't a test of this)

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[erezrokah]

Thanks @dfdez, I'm concerned that we might rely of that array to contain more than 1 element in a few places in the codebase.

For example with this change the CMS crashes in EditorControlPane.js

Do you mind looking at the error?

[dfdez]

Thanks @dfdez, I'm concerned that we might rely of that array to contain more than 1 element in a few places in the codebase.

For example with this change the CMS crashes in EditorControlPane.js

Do you mind looking at the error?

Sure!

[dfdez]

The problem was the i18n editor toggle, by having only 1 locale the editor tried to load locale[1] creating the problem showed above.

In a52ca73 I updated the EditorInterface.js to only show the toggle if i18n is enabled and there are multiple locales.

[dfdez]

Any news about this? @erezrokah

[martinjagodic]

@dfdez any reason why you closed this? This would be great to implement after we solve priority issues.

[dfdez]

I thought it was abandoned 🥲 but It can be reopened of course!

[martinjagodic]

Not abandoned, just in a long queue :D

[martinjagodic]

@dfdez can you solve merge conflicts, please? They appeared because packages and folders were renamed.