Fix the cloneSpecificRevision procedure

When cloning a specific revision we also must disable automatic line
endings conversions just like for the `doClone` procedure in the
previous commit.

Related to nim-lang#957

Author: bobeff

src/nimblepkg/download.nim

@@ -144,6 +144,7 @@ proc cloneSpecificRevision(downloadMethod: DownloadMethod,
     let downloadDir = downloadDir.quoteShell
     createDir(downloadDir)
     discard tryDoCmdEx(&"git -C {downloadDir} init")
+    discard tryDoCmdEx(&"git -C {downloadDir} config core.autocrlf false")
     discard tryDoCmdEx(&"git -C {downloadDir} remote add origin {url}")
     discard tryDoCmdEx(
       &"git -C {downloadDir} fetch --depth 1 origin {vcsRevision}")