[docs] Correct the link of Proposal SWT-0006

[lamtrinhdev]

Motivation:

Currently, we the link of SWT-0006 at 0006-return-errors-from-expect-throws.md that will display 404 Not Found . Correct the link of Proposal SWT-0006.

Modifications:

• Documentation/Proposals/0006-return-errors-from-expect-throws.md

Result:

Correct the link of Proposal SWT-0006

Checklist:

• Code and documentation should follow the style of the Style Guide.

[lamtrinhdev]

Dear @grynspan ,

I have a minor update at 0006-return-errors-from-expect-throws.md. Could you please help me to review it?

Thanks,
Lam

[grynspan]

Thanks for the fix! I'll merge it after the holiday break.