Upgrade MicroPython

[microbit-matt-hillsdon]

New releases:

• https://github.com/bbcmicrobit/micropython/releases/tag/v1.1.1
• https://github.com/microbit-foundation/micropython-microbit-v2/releases/tag/v2.1.1

Let's use this as a chance to document the process.

Simulator:

• [x] Review changelogs and diff to determine simulator changes, stubs changes any other documentation changes
• [x] Raise educational content impact to Foundation education team (likely already in hand or low priority)
• [x] Update simulator as required
• [x] Run through simulator examples in simulator demo.html
• [x] Test simulator in Python Editor (locally)
• [x] Merge simulator changes

Editor:

• [x] Update stubs as required
• [x] Update MicroPython hex files and version metadata in the editor
• [x] PR with updated sim (via staging) and stubs
• [x] Release stubs
• [x] Test and merge PR

Now or later:

• [ ] Release simulator
• [ ] Update and publish simulator versioning CloudFront function
• [ ] Release editor

[microbit-matt-hillsdon]

We've added an issue template similar to this on the PR above.

[microbit-matt-hillsdon]

This is now on the beta. We'll update the live editor later in the week.