Don't use hardcoded hostnames
This change corrects problems reported by the `yamllint` linter. Since key duplication problems were removed in 4d48711, this commit mainly fixes trailing spaces and extra empty lines at beginning/end of files.
4d48711
* Docs Networking tests * Copy networking tests from test-network-modules * Networking transport settings - group_vars * Network playbooks * Debug should be off by default * Update nxos.yaml * Remove items from top level * Use dependencies, not pre-tasks * Remove trailing blank lines * Remove backup files * newlines