fix: add SSH key fixtures and improve E2E test SSH connectivity

- Add testing SSH key pair in fixtures/ directory for CI/CD compatibility
- Update cloud-init.yml to use the new testing public key
- Modify e2e_tests.rs to copy SSH keys to temporary directory during tests
- Use temporary SSH keys instead of relying on local ~/.ssh/testing_rsa
- Add tempfile dependency for secure temporary directory management
- Suppress dead_code warning for temp_dir field (needed for directory lifetime)
- Add verbose logging for SSH key and temp directory paths

This resolves the SSH connectivity issue in GitHub Actions by providing
self-contained SSH keys that don't depend on local machine configuration.

Author: josecelano

fixtures/testing_rsa

@@ -0,0 +1,49 @@
+-----BEGIN OPENSSH PRIVATE KEY-----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=
+-----END OPENSSH PRIVATE KEY-----

fixtures/testing_rsa.pub

@@ -0,0 +1 @@
+ssh-rsa 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 testing@torrust-testing-infra