cffr 1.1.0

• Now cffr adds automatically dois to packages on CRAN (e.g.
  https://doi.org/10.32614/CRAN.package.cffr):
  • If the package has a CITATION file providing a doi, the CITATION doi
    would be used as the main CITATION.cff doi and the CRAN doi
    would be added as an identifier.
  • Otherwise, CRAN doi would be used as doi.
  • When extracting dependencies (e.g cff_create(dependencies = TRUE) and
    the package dependency is on CRAN, the CRAN doi would be used
    for the dependency in the references key.
• Extract commit from RemoteSha.
• Update cran_to_spdx dataset.

What's Changed

• Extract commit info by @dieghernan in #72
• Fix action for testing cffr in ~2500 packages by @dieghernan in #73
• Recognize CRAN DOI by @dieghernan in #75

Full Changelog: v1.0.1...v1.1.0