feat: update to new Vue grammar scope name

[KammererTob]

This PR adjusts the graphql grammar to work with the new Vue grammar scope name.
Starting with version 3.2.0 of the Vue language tools the scope name was changed to "text.html.vue" instead of "source.vue" (See: vuejs/language-tools#5856).

I am not sure if the addition in the injectionSelector is necessary, since in my testing i did not notice any difference, so maybe someone more knowledgeable can give me guidance on this.

Closes: vuejs/language-tools#5969

[changeset-bot]

🦋 Changeset detected

Latest commit: cf01e19

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
vscode-graphql-syntax	Patch

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[KammererTob]

Just noticed that there already is a PR open for this: #4144

Feel free to close mine if you choose to go with that earlier one. Keeping this open just for visibility, since this completely breaks the Syntax Highlighting for Vue files at the moment.

[outluch]

All checks passed, everything is ready. Please, merge this.
Vue + graphql (hasura) is heaven.

[trevor-scheer]

Thanks @KammererTob, I'm going to land the other one once I've got maintainer permissions sorted. Feel free to close this if you like, else I will once it lands.

Edit: this one's actually got a changeset while the other doesn't, so if the other isn't fixed once I have permissions then I may just merge this one. Maybe leave it open for now 😄.