To reproduce:
1) Open Unity Hub
2) Install Unity with Linux Support

Expected: The support is installed in {UNITY_PATH}/PlaybackEngines/LinuxStandaloneSupport
Actual: It's installed in {UNITY_PATH}

Reproduced with 2019.3.0a8, 2019.3.0b5 and 2020.1.0a5 installations
Not reproduced with 2019.2.8f1 and 2019.3.0a7 installation

Workaround:
- open install location
- create directory `PlaybackEngines/LinuxStandaloneSupport`
- move files and dirs from install root to new dir:
- Variations
- Whitelists
- modules.asset
- UnityEditor.LinuxStandalone.Extensions.dll
- UnityEditor.LinuxStandalone.Extensions.pdb​
- reopen unity