docs: update raspberry pi section

[jrriehl]

Proposed changes

Raspberry Pi section needs an update both for manual installation and for using the new hosted image.

Checklist

Put an x in the boxes that apply.

• [ ] I have read the CONTRIBUTING doc
• [ ] I am making a pull request against the develop branch (left side). Also you should start your branch off our develop.
• [ ] Lint and unit tests pass locally with my changes and CI passes too
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] I have checked that code coverage does not decrease.
• [ ] I have added necessary documentation (if appropriate)
• [ ] Any dependent changes have been merged and published in downstream modules

Further comments

If this is a relatively large or complex change, kick off the discussion by explaining why you chose the solution you did and what alternatives you considered, etc...

DELETE INCLUSIVE THIS AND BELOW FOR STANDARD PR

Release summary

Version number: [e.g. 1.0.1]

Release details

Describe in short the main changes with the new release.

Checklist

Put an x in the boxes that apply.

• [ ] I have read the CONTRIBUTING doc
• [ ] I am making a pull request against the main branch (left side), from develop
• [ ] Lint and unit tests pass locally and in CI
• [ ] I have checked the fingerprint hashes are correct by running (scripts/generate_ipfs_hashes.py)
• [ ] I have regenerated the latest API docs
• [ ] I built the documentation and updated it with the latest changes
• [ ] I have added an item in HISTORY.md for this release
• [ ] I bumped the version number in the aea/__version__.py file.
• [ ] I bumped the version number in every Docker image of the repo and published it. Also, I built and published them with tag latest
  (check the READMEs of aea-develop and aea-user)
• [ ] I have pushed the latest packages to the registry.
• [ ] I have uploaded the latest aea to PyPI.
• [ ] I have uploaded the latest plugins to PyPI.

Further comments

Write here any other comment about the release, if any.

[github-actions[bot]]

Visit the preview URL for this PR (updated for commit 5aad54c):

https://fetch-docs-preview--pr2806-docs-raspberry-pi-isuo5oyi.web.app

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[codecov-commenter]

Codecov Report

Merging #2806 (0a59e38) into develop (ef04074) will increase coverage by 0.01%. The diff coverage is 98.68%.

:exclamation: Current head 0a59e38 differs from pull request most recent head 5aad54c. Consider uploading reports for the commit 5aad54c to get more accurate results

@@             Coverage Diff             @@
##           develop    #2806      +/-   ##
===========================================
+ Coverage    97.88%   97.90%   +0.01%     
===========================================
  Files          506      503       -3     
  Lines        36146    35849     -297     
===========================================
- Hits         35382    35098     -284     
+ Misses         764      751      -13     

Flag	Coverage Δ
unittests	97.90% <98.68%> (+0.01%)	:arrow_up:

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
aea/cli/run.py	83.33% <0.00%> (ø)
aea/crypto/registries/base.py	100.00% <ø> (ø)
aea/helpers/async_utils.py	100.00% <ø> (ø)
aea/helpers/install_dependency.py	100.00% <ø> (ø)
aea/helpers/transaction/base.py	100.00% <ø> (ø)
aea/launcher.py	100.00% <ø> (ø)
aea/runtime.py	98.20% <ø> (ø)
packages/fetchai/connections/oef/connection.py	100.00% <ø> (ø)
...tchai/connections/p2p_libp2p/check_dependencies.py	100.00% <ø> (ø)
...kages/fetchai/connections/p2p_libp2p/connection.py	100.00% <ø> (ø)
... and 76 more

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