`lint_xxx()` functions use incorrect pattern for searching paths

[ErdaradunGaztea]

The current pattern doesn't check for the end of file name, which caused my call to try reading .Rproj and sysdata.rda files. A $ added at the end should do the trick.

(Sorry for not being more detailed, I'm on my phone in the middle of uni course currently)

[hadley]

Thanks for reporting this!

[AshesITR]

I will resolve this with a PR updating the lint functions to lintr >= 3.0.0