changed cover link: yearn-wants-to-buy-your-YFI

[RestlessMike]

Description

Please include a summary of the change and which issue is fixed.
Please also include relevant motivation and context.

This pull request ...

Fixed issue

Please indicate the fixed issues with this exact format Fixes #232 where 232 is the number of the issue. This will trigger an auto-close if the issue when this PR is merged.
Supported keywords:

Fixes #1,#2,#3
close #1, #2, #3
fix #1 #2 #3
resolve #1,#2 #3
Resolves: #1,#2,#3
closed : #1, #2, #3

Fixes #(issue)

Type of change

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• Add a new article/page
• Fix a Typo
• Add a new translation
• Other

Resources

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