Sscc2024 materials to tutorials list

[attesillanpaa]

Proposed changes

Briefly describe the changes you've made here: added a link to zenodo summary of the spring school materials in the tutorials list and a corresponding what's new entry.

See proposed content here:

• https://csc-guide-preview.rahtiapp.fi/origin/sscc2024/support/whats-new/#training-tutorials
• https://csc-guide-preview.rahtiapp.fi/origin/sscc2024/support/tutorials/

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• [x] I have followed the instructions in the Contributing and Styleguide documents.
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• [x] I have included a link to the appropriate preview page (select your branch from the list).