Addon-docs: Angular empty string now infers to "string" instead of "void"

[activenode]

Issue: #12986

What I did

• I added a test for an empty string to make sure it's covered: ['', { name: 'string' }]
• I fixed the extractTypeFromValue function to verify that when valueType == string it will infer a string

How to test

Test is added. Should be covered now. For testing if the issue is fixed please refer to the description in the issue.

[shilman]

Looks good. Merging for now, but are there more types that need improved inference? Any chance you can put together a followup @activenode ?

[activenode]

I can do a follow-up.

[activenode]

I also found that the test was put in the wrong place and it should've failed (seems to have slipped in).
Will immediately create a follow-up PR to fix this.

(it is adding the test in the with compodoc type but it should be exactly in the without compodoc type).

So just the test is wrong but still it needs to be fixed. See #13009