chore(release): 0.21.0 [skip ci]

# [0.21.0](https://github.com/saltstack-formulas/systemd-formula/compare/v0.20.0...v0.21.0) (2021-10-09)

### Bug Fixes

* **rsync_test_package:** use correct package for Gentoo ([b7877138](https://github.com/saltstack-formulas/systemd-formula/commit/b787713805d4a7c9f9efdd0e3de6123f2b3cd534))

### Continuous Integration

* **gitlab-ci:** enable all `master` platforms except `oraclelinux-7` ([ad867bb7](https://github.com/saltstack-formulas/systemd-formula/commit/ad867bb701f43c63ca6ee49525d4b47dc28cd4c0))

### Features

* **os*map.yaml:** restructure across all platforms ([10a6c241](https://github.com/saltstack-formulas/systemd-formula/commit/10a6c241d38c040825c3b6b22c7223ebe9a50041))
* **wait_online:** use separate `enabled` & `running` states ([a42fa971](https://github.com/saltstack-formulas/systemd-formula/commit/a42fa9711b1be4e6594a3819b206bcdeeacdc297))