Update "develop" branch publish workflow to use source from "develop" of spdx-spec & spdx-3-model

[bact]

Background

• Branch structure/name changes
• New spec-parser CLI
  • Position of input directory is changed and specifying the output directory requires an option -o
  • The current command line no longer works (The publication workflow is failed: see this run)

What this PR does?

• Updating the workflow in the "develop" branch to use the source from spdx-3-model "develop" branch.
• Updating command line for spec-parser
  • As we can specify output directories, some of the copy steps are no longer necessary and now removed

Similar PRs

Similar changes, after minor branch customization, will be applied to three branches:

1. spdx-spec "develop" + spdx-3-model "develop" --> https://spdx.github.com/spdx-spec/v3.1-dev/
   • This PR
2. spdx-spec "main" + spdx-3-model "main" --> https://spdx.github.com/spdx-spec/v3.0.1/
   • Update "main" branch publish workflow to use source from "main" of spdx-spec & spdx-3-model #1183
3. spdx-spec "support/3.0" + spdx-3-model "support/3.0" --> https://spdx.github.com/spdx-spec/v3.0.x-dev/
   • a PR to be created

Demo

https://bact.github.io/spdx-spec/v3.1-dev/model/Core/Classes/Agent/

Notice the "Class hierarchy" heading, which is from the latest spec-parser.

More

• See full discussion, also about the target URL name, in Publication source branches/tags and target URLs mapping/aliases #1155
• The new spec-parser command line also got updated in the build doc by Update build doc for new spec-parser options #1186