scripts/repo-install-test: fix sftp compat, part 2

Copy files inside repo-install-test, instead of copying the directory
again. Otherwise it creates a /repo-install-test/repo-install-test/ path
inside qemu and then fails to run the script inside the directory:

Fix for:
  sh: 0: cannot open /repo-install-test/run-inside-env.sh: No such file

Fixes: a7791217 ("scripts/repo-install-test: fix sftp compat")
Change-Id: I04d8c0e0fd31ee5d2a0912300dc93f5339bbef11
1 file changed