[html] suggest `_self` and `_blank`

[mohamad228]

hi i have problem with some attribute
forb example in target attribute didnt suggest me
_self or _parent _blank
even with ctrl space

• language is on html

[rzhao271]

I still don't see those suggestions when I start typing <a href="test" target="

[aeschli]

Oh, I forgot to publish a new version of vscode-custom-data

[aeschli]

Updated through 66b9a8a