feat(docker): Add ssh-client to Docker image to access private modules via ssh (#553)

.github/.container-structure-test-config.yaml

@@ -73,6 +73,11 @@ commandTests:
     command: "su-exec"
     expectedOutput: ["^Usage: su-exec user-spec command \\[args\\]\\n$"]
 
+  - name: "ssh"
+    command: "ssh"
+    args: [ "-V" ]
+    expectedError: ["^OpenSSH_9\\.[0-9]+"]
+
 fileExistenceTests:
   - name: 'terrascan init'
     path: '/root/.terrascan/pkg/policies/opa/rego/github/github_repository/privateRepoEnabled.rego'