Add Vue context to computed options type (fix #10878)

[okj579]

Vue passes the Vue object as the first parameter, which is useful for arrow functions. This change reflects that in the types.

Fixes #10878

What kind of change does this PR introduce? (check at least one)

• Bugfix
• Feature
• Code style update
• Refactor
• Build-related changes
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Does this PR introduce a breaking change? (check one)

• Yes
• No

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• New/updated tests are included

If adding a new feature, the PR's description includes:

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Other information:

[posva]

Thank you but this is not exactly what should be passed. What should be passed is the type of the component to get access to other data and computed properties. Note it might not be possible to support fully so the issue might not be really fixable.