Bump doc requirements for successful build

[merelcht]

Description

Fix kedro-org/kedro#3774

Development notes

Updated doc requirements to make sure docs in a new project can be built successfully. Same fix done on the main repo side: kedro-org/kedro#3998

How has this been tested?

Manually created kedro projects and followed the steps outlined in kedro-org/kedro#3774 both with and without examples.

kedro new #... enable docs, enter the project
pip install -e '.[docs]'
mkdir docs/_build
python -m sphinx docs/source docs/_build

Checklist

• Opened this PR as a 'Draft Pull Request' if it is work-in-progress
• Assigned myself to the PR
• Added tests to cover my changes