Update updating.markdown

[ge2rt]

Proposed change

Minor textual fixes and readability improvements.

Type of change

• [ x] Spelling, grammar or other readability improvements (current branch).
• Adjusted missing or incorrect information in the current documentation (current branch).
• Added documentation for a new integration I'm adding to Home Assistant (next branch).
• Added documentation for a new feature I'm adding to Home Assistant (next branch).
• Removed stale or deprecated documentation.

Additional information

Question: Is the part for the Raspberry Pi Docker container also correct for a RasPi 4? The 'docker pull' commands suggests it's for a RasPi 3...

• Link to parent pull request in the codebase:
• This PR fixes or closes issue:

Checklist

• [ x] This PR uses the correct branch, based on one of the following:
  • I made a change to the existing documentation and used the current branch.
  • I made a change that is related to an upcoming version of Home Assistant and used the next branch.
• [ x] The documentation follows the Home Assistant documentation standards.

[frenck]

Thanks, @ge2rt! 👍