errors: raise RemoteError in some places in exchange.py

mercurial/exchange.py

tests/test-bookmarks-pushpull.t

tests/test-bundle2-exchange.t

tests/test-bundle2-remote-changegroup.t

tests/test-clone-uncompressed.t

tests/test-http.t

tests/test-lfs-serve.t

tests/test-narrow-clone-stream.t

tests/test-narrow-pull.t

tests/test-narrow-shallow.t

tests/test-remotefilelog-clone-tree.t

tests/test-remotefilelog-clone.t

tests/test-ssh.t