feat: bump eslint ecmaVersion to 2020

[josefaidt]

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Description

reference #2984

Bumps eslint ecmaVersion to 2020, enables usage of import.meta.env in JS files without error

[changeset-bot]

🦋 Changeset detected

Latest commit: 24c0e52

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

This PR includes changesets to release 1 package

Name	Type
create-svelte	Patch

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[bluwy]

Is this ready for review? From a glance it looks good to me. We may want a changeset for this as well.

[josefaidt]

Hey @bluwy I think it's ready for review! I was a bit hesitant to open the PR for review prior to the corresponding issue triage/discussion

[bluwy]

I have not verified the linting error myself, so I'm trusting that this fixes it :) But I don't think it would hurt either way since 2022 is just around the corner.

[benmccann]

we set everything to es2020 in #2604, but looks like this was a place that got overlooked

[benmccann]

instead of reference #2984 if you say fixes #2984 or closes #2984 then github will link the issue and PR to automatically close the issue when the PR is merged