Fix anchor links in README

[gdalmau]

Pull Request check-list

Please make sure to review and check all of these items:

• Does $ tox pass with this change (including linting)?
• Do the CI tests pass with this change (enable it first in your forked repo and wait for the github action build to finish)?
• Is the new or changed code fully tested?
• Is a documentation update included (if this change modifies existing APIs, or introduces new ones)?

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Description of change

The anchor links in the README don't seem to work. Removing one # should fix it.

[chayim]

@gdalmau Thank you so much for contributing this! I've already got it fixed, and queued up for tomorrow (literally), in this PR.

[gdalmau]

@chayim Oh I see 😄 then I will close it.

Superseded by #1743