tests: clone the repo over ssh in tests/test-logexchange.t

Cloning a local repo in tests, and normally too does not perform the actual
clone, rather it copies the file contents. This makes remotenames information
not being transferred. Let's clone over ssh so that we can test remotenames
correctly.

Differential Revision: https://phab.mercurial-scm.org/D3519

tests/test-logexchange.t

@@ -2,6 +2,8 b' Testing the functionality to pull remote'
 =============================================
 
   $ cat >> $HGRCPATH << EOF
+  > [ui]
+  > ssh = $PYTHON "$TESTDIR/dummyssh"
   > [alias]
   > glog = log -G -T '{rev}:{node|short}  {desc}'
   > [experimental]
@@ -52,7 +54,13 b' Making a client repo'
 
   $ cd ..
 
-  $ hg clone server client
+  $ hg clone ssh://user@dummy/server client
+  requesting all changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 9 changesets with 9 changes to 9 files (+1 heads)
+  new changesets 18d04c59bb5d:3e1487808078
   updating to branch default
   8 files updated, 0 files merged, 0 files removed, 0 files unresolved