Deprecate github formatter usage in script lint:ci.

[junhaoliao]

Request

#66 added Stylelint for lint checking CSS files in the "new-log-viewer" and a corresponding workflow, which worked with Stylelint's github formatter. However, it was understood that the github formatter has been deprecated and will be removed in a future Stylelint release.

Possible implementation

We attempted to add a problem matcher for matching Stylelint's default "string" formatter's output, but it did not work back then because:

1. The "new-log-viewer" files were placed in a subfolder projectRoot/new-log-viewer.
2. However, when the Stylelint command is run, it only produces relative paths. Previously, the command was run inside the subfolder, which is different from the project root.
3. Till this day, for GitHub problem matchers, there is no way to specify a working directory to correctly resolve any relative paths, so that the problem matcher can identify the files and lines whenever there are failures corresponded to the relative paths.

#101 moved all "new-log-viewer" files to the root directory which resolved above concerns and made the problem-matcher approach viable.

[junhaoliao]

Fixed by #112 . Closing this issue now