[Snyk] Upgrade @ethersproject/bignumber from 5.5.0 to 5.7.0

[swirlds-automation]

Snyk has created this PR to upgrade @ethersproject/bignumber from 5.5.0 to 5.7.0.

:information_source: Keep your dependencies up-to-date. This makes it easier to fix existing vulnerabilities and to more quickly identify and fix newly disclosed vulnerabilities when they affect your project.

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• The recommended version is 4 versions ahead of your current version.

• The recommended version was released on 2 years ago.

Release notes

Package name: @ethersproject/bignumber

• 5.7.0 - 2022-08-19
• 5.6.2 - 2022-05-24
• 5.6.1 - 2022-05-14
• 5.6.0 - 2022-03-10
• 5.5.0 - 2021-10-20

from @ethersproject/bignumber GitHub release notes

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[!IMPORTANT]

• Check the changes in this PR to ensure they won't cause issues with your project.
• This PR was automatically created by Snyk using the credentials of a real user.

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