Not sure why the unchanged files appear in the pending change list in your case. This is normal if a file becomes automatically checked out due to a change, and if ultimately the contents of the file are changed back to it's original state.
As a workaround to ignore the annoying phenomenon, you could use tfpt uu . /noget /recursive $(SolutionDir)
command through TFS Power Tools. More details please refer this similar question: Visual Studio TFS shows unchanged files in the list of pending changes
However, there are no Power Tools for Team Foundation Server 2017
Workaround: We are excited to let you know that most of the previous Power Tools have been integrated into TFS 2017. The Process
Template Editor is one that has not been integrated, but we are going
to publish a Process Template Editor tool for TFS 2017 to the Visual
Studio Gallery shortly after TFS 2017 is available. We will provide
the link here as soon as it’s published.
Source Link
Otherwise, just check in these files or undo them manually.