docs: add documentation for the --destination flag

[nils-van-zuijlen]

Related to #217, #733

Description

Add documentation for the --destination flag to the readme.

Submitter Checklist

These are the criteria that every PR should meet, please check them off as you
review them:

• Includes unit tests (Not needed for documentation?)
• Adds integration tests if needed. (Not needed)

See the contribution guide for more details.

Reviewer Notes

• The code flow looks good.
• Unit tests and or integration tests added.

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[nils-van-zuijlen]

I unfortunately am not able to sign the CLA because I do not want a Google account, but I hereby set this commit in the public domain. Feel free to take its content in another MR by yourself, see ya!

[JeromeJu]

I unfortunately am not able to sign the CLA because I do not want a Google account, but I hereby set this commit in the public domain. Feel free to take its content in another MR by yourself, see ya!

Thanks @nils-van-zuijlen for this PR - would you mind trying signing the CLA not via corporate contributor but via individual contributor? In that way you might not need to opt for the way to have a google account.