🔨 CI: LLS should only be run if there are Lua file changes

[zach2good]

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Describe the feature

By its very nature, LLS takes a long time to run. We want it to be run when there are Lua changes, but it's a pain in the ass that we have to wait the what, 25 minutes? for it to run when there's a 1-line C++ change etc.

We collect the files changed in a PR, so we could be interrogating that and skipping/auto-passing that job