Use major version ref of editorconfig-checker/action-editorconfig-checker action

The editorconfig-checker/action-editorconfig-checker action is used in the "Check General Formatting" GitHub Actions
workflow as a convenient way to install the editorconfig-checker tool.

A major version ref is provided by the maintainers of that repository. It will always point to the latest release of the
2.x major version series.

Use of the major version ref will cause the workflow to use a stable version of the action, while also benefiting from
ongoing development to the action up until such time as a new major release of an action is made. At that time we would
need to evaluate whether any changes to the workflow are required by the breaking change that triggered the major
release before manually updating the major ref (e.g., `uses: editorconfig-checker/action-editorconfig-checker@v2` ->
`uses: editorconfig-checker/action-editorconfig-checker@v3`). I think this major version ref approach to action
dependency management strikes the right balance between stability and maintainability for this type of workflow.

Author: per1234

.github/workflows/check-general-formatting.yml

@@ -19,7 +19,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Install editorconfig-checker
-        uses: editorconfig-checker/action-editorconfig-checker@v2.0.0
+        uses: editorconfig-checker/action-editorconfig-checker@v2
 
       - name: Check formatting
         run: editorconfig-checker