Handle cases when getBlockType returns undefined

[mcliwanow]

What?

Added a few checks to determine if result of getBlockType is defined.

Why?

As reported in #34462 , getBlockType selector might return undefined and in few places it was assumed that it would return an object.

How?

In places that were assuming that result of getBlockType is an object I have added some checks to make sure that case when it's undefined is handled too.

I get no errors on the console but I see a "null" block after running wp.data.dispatch('core/blocks').removeBlockTypes('core/missing') and clicking on the block. Not sure if it's correct or not.

Testing Instructions

Test instructions can be found here.

Note
If someone could confirm that default values returned in those 2 places are correct it would be perfect 🙏

• 69faa93#diff-6b8a8712230f209945133ddda4688f21090127c9fd9f885e988579020b3426a6R97
• 69faa93#diff-9740c1068259d4fb58036de0b2fa8a58ba9bb83f0c4b7c85aee6c0835698accaR365

[jorgefilipecosta]

The changes look good to me 👍