docs: Update docs deployment workflow actions

[toshify]

Because GitHub has updated the default node version and our deployment workflow fails

this commit will:

• update the workflow with the latest version of actions
• set the node version used to latest long term support version

Certification

• [X] I certify that
• I have read the contributing guidelines
• I license these contributions to the public under Seedling's LICENSE and have the rights to do so.

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