ci: ignore host-key change in CI-ssh server

.appveyor.yml

@@ -277,6 +277,8 @@ for:
       - mkdir ~/DLTMP && export TMPDIR=~/DLTMP
       # establish a root directory for SSH tests
       - "mkdir ${DATALAD_TESTS_SERVER_LOCALPATH}"
+      # allow SSH access if the host key has changed
+      - echo StrictHostKeyChecking no >> ~/.ssh/config
 
     install:
       # verify that a PY variable is declared that identifies the desired Python version