Add python path in cmake commands in Github Actions

[lauramurgatroyd]

Description

When ubuntu-latest updated to 24.04.1 the actions stopped working (#2017). The reason was due to the same cmake error we saw on linux and windows when trying to build cil locally. I updated the cmake commands in the actions to contain the path to the python executable, which is the same fix we did in our instructions for cmake in the README.

We are not going to update to ubuntu-latest yet, see issue here: #2017

Example Usage

Changes

Testing you performed

Please add any demo scripts to https://github.com/TomographicImaging/CIL-Demos/tree/main/misc

Related issues/links

Checklist

• I have performed a self-review of my code
• I have added docstrings in line with the guidance in the developer guide
• I have updated the relevant documentation
• I have implemented unit tests that cover any new or modified functionality
• CHANGELOG.md has been updated with any functionality change
• Request review from all relevant developers
• Change pull request label to 'Waiting for review'

Contribution Notes

Please read and adhere to the developer guide and local patterns and conventions.

• The content of this Pull Request (the Contribution) is intentionally submitted for inclusion in CIL (the Work) under the terms and conditions of the Apache-2.0 License
• I confirm that the contribution does not violate any intellectual property rights of third parties

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