Add troubleshooting section to pip install issues with outdated pip version (#6956)

### What

*  half of #6931
* still unclear where the reported black screen on windows comes from

### Checklist
* [x] I have read and agree to [Contributor
Guide](https://github.com/rerun-io/rerun/blob/main/CONTRIBUTING.md) and
the [Code of
Conduct](https://github.com/rerun-io/rerun/blob/main/CODE_OF_CONDUCT.md)
* [x] I've included a screenshot or gif (if applicable)
* [x] I have tested the web demo (if applicable):
* Using examples from latest `main` build:
[rerun.io/viewer](https://rerun.io/viewer/pr/6956?manifest_url=https://app.rerun.io/version/main/examples_manifest.json)
* Using full set of examples from `nightly` build:
[rerun.io/viewer](https://rerun.io/viewer/pr/6956?manifest_url=https://app.rerun.io/version/nightly/examples_manifest.json)
* [x] The PR title and labels are set such as to maximize their
usefulness for the next release's CHANGELOG
* [x] If applicable, add a new check to the [release
checklist](https://github.com/rerun-io/rerun/blob/main/tests/python/release_checklist)!
* [x] If have noted any breaking changes to the log API in
`CHANGELOG.md` and the migration guide

- [PR Build Summary](https://build.rerun.io/pr/6956)
- [Recent benchmark results](https://build.rerun.io/graphs/crates.html)
- [Wasm size tracking](https://build.rerun.io/graphs/sizes.html)

To run all checks from `main`, comment on the PR with `@rerun-bot
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Author: Wumpf

docs/content/getting-started/troubleshooting.md

@@ -63,6 +63,21 @@ Since the Mesa driver on WSL dispatches to the Windows host graphics driver, it
 For example, [line rendering issues](https://github.com/rerun-io/rerun/issues/6749) have been observed when running from WSL with an
 outdated AMD driver on the Windows host.
 
+## `pip install` issues
+
+If you see the following when running `pip install rerun-sdk` or `pip install rerun-notebook` on a supported platform:
+
+```sh
+ERROR: Could not find a version that satisfies the requirement rerun-sdk (from versions: none)
+ERROR: No matching distribution found for rerun-sdk
+```
+
+Then this is likely because you're running a version of pip that is too old.
+You can check the version of pip with `pip --version`.
+If you're running a version of pip 20 or older, you should upgrade it with `pip install --upgrade pip`.
+⚠️ depending on your system configuration this may upgrade the pip installation aliased by `pip3` instead of `pip`.
+
+
 ## Startup issues
 
 If Rerun is having trouble starting, you can try resetting its memory with: