Enable require_checksum by default

[suzuki-shunsuke]

Feature Overview

Enable require_checksum by default.

Why is the feature needed?

Please explain the problem you want to solve.

To enforce the checksum verification and improve the security.
Checksum Verification has a trade off between security and user experience.
require_checksum was disabled for user experience, but I think we should make require_checksum enabled by default from aqua v2.

require_checksum will be changed from aqua v2.

• Change the behaviour of require_checksum #1656

Note that checksum verification is still disabled by default.
I think it is a bit difficult to enable checksum verification by default in terms of user experience.
Unfortunately, many users don't think checksum verification is mandatory.

Does the feature include Breaking Changes?

Yes.

Example Code

command and configuration

$ 

[suzuki-shunsuke]

• feat: enable require_checksum by default #1686

[suzuki-shunsuke]

We changed the mind and decided to disable require_checksum by default.

• Support configuring require_checksum by the environment variable #1781