Metadata DB Upload: Model SBD not being interpreted

[CodeGat]

See the two spaces between ./metadata/output and mom5 here and the interpretation of mom5 as the model name here.

This is due to ${{ inputs.root-sbd }} not interpreting the default: ${{ inputs.model }} here. There are no errors noting that this doesn't work, but GitHubs own documentation notes that it must be a string. Indeed, we cannot have dynamic defaults yet.

• Update the workflow so the inputs.root-sbd has a sensible default.
• Add to the devdocs this interesting fact

[CodeGat]

See https://github.com/ACCESS-NRI/dev-docs/wiki/Continuous-integration-and-deployment#dynamic-defaults-in-inputs for the devdocs link