Reproduction steps:
1. Create a new project.
2. Switch platform to iOS in the Build Settings.
3. Go to Player Settings.
4. Uncheck the 'Automatically Sign' checkbox.
5. Set Bundle Identifier.
5. Input 'Signing Team ID' (Tested ID provided in the edit below).
6. On the right of 'iOS Provisioning Profile' Click 'Browse'.
7. Navigate and select a provisioning profile (Tested with '~/Library/MobileDevice\Provisioning Profiles').
8. Set 'Profile Type' to 'Development'.
9. Go to Build Settings and click 'Build and Run'.

Actual behavior:
- Xcode build fails with error messages:

= 2018.2.0a3 - 2018.2.0a8:
No certificate for team '' matching 'iPhone Development' found
Select a different signing certificate for CODE_SIGN_IDENTITY, a team that matches your selected certificate, or switch to automatic provisioning.
Provisioning profile "iOS Team Provisioning Profile: com.Company.ProductName" is Xcode managed, but signing settings require a manually managed profile.

= 2018.1.0a6 - 2018.1.0f1, 2018.2.0a1 - 2018.2.0a2:
Provisioning profile "iOS Team Provisioning Profile: com.Company.ProductName" is Xcode managed, but signing settings require a manually managed profile.

Not reproducible with:
2018.1.0a5

Note:
- It may be 2 separate issues.