Create change files for changes since the last release

[anomiex]

Changes proposed in this Pull Request:

For everything other than the Jetpack plugin, I created a change file
for any commit touching the project that didn't already have one.

For Jetpack, I did a final pass through the "Needs Changelog" tag and
added a change file for each PR found.

Jetpack product discussion

There's probably a ticket somewhere.

Does this pull request change what data or activity we track or use?

No.

Testing instructions:

• Proofread the files.

[github-actions]

Thank you for your PR!

When contributing to Jetpack, we have a few suggestions that can help us test and review your patch:

• ✅ Include a description of your PR changes.
  
• ✅ All commits were linted before commit.
  
• ✅ Add a "[Status]" label (In Progress, Needs Team Review, ...).
  
• ✅ Add testing instructions.
  
• ✅ Specify whether this PR includes any changes to data or privacy.
  

This comment will be updated as you work on your PR and make changes. If you think that some of those checks are not needed for your PR, please explain why you think so. Thanks for cooperation 🤖

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If you are an automattician, once your PR is ready for review add the "[Status] Needs Team review" label and ask someone from your team review the code.
Once you’ve done so, switch to the "[Status] Needs Review" label; someone from Jetpack Crew will then review this PR and merge it to be included in the next Jetpack release.undefined

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beta plugin:

• Next scheduled release: April 6, 2021.
• Scheduled code freeze: March 29, 2021

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jetpack plugin:

• Next scheduled release: April 6, 2021.
• Scheduled code freeze: March 29, 2021

[kraftbj]

To confirm, once this is merged, we can delete the "{Has|Needs} Changelog" labels, correct?

[anomiex]

To confirm, once this is merged, we can delete the "{Has|Needs} Changelog" labels, correct?

Yeah, I'd think so. All the "Needs Changelog" have already been removed from tasks as I put them in this PR.

Changes made