Split CI into reusable actions #2

Job	Run time
Flake Checks 📋 / Find Checks 🔍	8s
Build Tarballs 🛠️ / Build 🛠️ (modern)	5m 2s
Build Tarballs 🛠️ / Build 🛠️ (legacy)	4m 23s
Build Tarballs 🛠️ / Build 🛠️ (test)	3m 47s
Flake Checks 📋 / Check 📋 (nixpkgs-fmt)	18s
Flake Checks 📋 / Check 📋 (rustfmt)	34s
Flake Checks 📋 / Check 📋 (shfmt)	15s
Flake Checks 📋 / Check 📋 (side-effects)	24s
Flake Checks 📋 / Check 📋 (test-native-utils)	1m 4s
Flake Checks 📋 / Check 📋 (username)	1m 33s
Tests 🧪 / Find Tests 🔍	6s
Tests 🧪 / Test 🧪 (tests/systemd-services.Tests.ps1, ubuntu-20.04)	1m 8s
Tests 🧪 / Test 🧪 (tests/basic-functionality.Tests.ps1, ubuntu-20.04)	2m 6s
Tests 🧪 / Test 🧪 (tests/systemd-user.Tests.ps1, ubuntu-20.04)	1m 6s
Tests 🧪 / Test 🧪 (tests/docker/docker.Tests.ps1, ubuntu-20.04)	1m 52s
Tests 🧪 / Test 🧪 (tests/exit-codes.Tests.ps1, ubuntu-20.04)	59s
Tests 🧪 / Test 🧪 (tests/login-shell/login-shell.Tests.ps1, ubuntu-20.04)	1m 42s
Tests 🧪 / Test 🧪 (tests/username-change/username-change.Tests.ps1, ubuntu-20.04)	1m 30s
Tests 🧪 / Test 🧪 (tests/shells.Tests.ps1, ubuntu-20.04)	3m 34s
	31m 31s

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