title: SSH auth fails with "Host key verification failed" despite providing valid keys
body: <p>In Azure DevOps Pipelines I want to SSH to a private repo with dependencies. I am getting following error:</p>
  
  <blockquote>
    <p>Host key verification failed. fatal: Could not read from remote repository.</p>
  </blockquote>
  
  <p>Despite uploading private key to secure files and public key is set in project variables.</p>
  
  <p>see below</p>
  
  <pre><code>steps:  
  - task: InstallSSHKey@0
    inputs:
      hostName: $(hostname)
      sshPublicKey: $(testkey.pub)
      sshPassphrase: $(passphrase)
      sshKeySecureFile: testkey
  
  
  - script: |
      git clone git@github.xxxxxx.com:xxxx/xxxxx.git
    displayName: 'clone repo' 
  </code></pre>