[ci] Add check_format parameter to LLS argument to restore json output

[claywar]

I affirm:

• I understand that if I do not agree to the following points by completing the checkboxes my PR will be ignored.
• I understand I should leave resolving conversations to the LandSandBoat team so that reviewers won't miss what was said.
• I have read and understood the Contributing Guide and the Code of Conduct.
• I have tested my code and the things my code has changed since the last commit in the PR and will test after any later commits.

What does this pull request do?

With recent LLS changes, the default output format was changed in cases where a new parameter (check_format) was added, and we do not explicitly set check_out_path (see: LuaLS/lua-language-server#3051)

Adds check_format parameter to LLS call in CI to move back to json output and fixes CI failures.

Steps to test these changes

CI should not fail on non-existing file.