Linting failing on main branch after PR merge commits

[alexanderianblair]

The Lint workflow is currently failing on the main branch after being triggered by a PR merge commit, with the following error:

  2024-07-17 10:26:17 [INFO]   --------------------------------------------
  2024-07-17 10:26:17 [INFO]   Gathering GitHub information...
  2024-07-17 10:26:17 [INFO]   Successfully validated GITHUB_WORKSPACE: /github/workspace
  2024-07-17 10:26:17 [INFO]   Successfully found GITHUB_EVENT_PATH: /github/workflow/event.json]
  2024-07-17 10:26:17 [INFO]   Successfully found GITHUB_SHA: e9b88d3995fb6e4c701f4f5bb2dd90d52c49f761
  2024-07-17 10:26:17 [INFO]   Successfully found GITHUB_PUSH_COMMIT_COUNT: 20
  fatal: ambiguous argument 'HEAD~20': unknown revision or path not in the working tree.
  Use '--' to separate paths from revisions, like this:
  'git <command> [<revision>...] -- [<file>...]'
  2024-07-17 10:26:17 [FATAL]   Failed to initialize GITHUB_BEFORE_SHA for a push event. Output: HEAD~20
  /action/lib/linter.sh: line 720: SUPER_LINTER_PRIVATE_OUTPUT_DIRECTORY_PATH: unbound 

Attempts to fix by changing the version of Super-Linter used in the workflow, in #12 and #13, have run the Lint workflow successfully on merge to main, but have failed on all subsequent merge commits.

The Lint workflow does appear to run correctly in PRs, however, and is providing useful checks.

[alexanderianblair]

Closing as this now seems to have been resolved following the update to Super Linter v6.7.0