qtbase-abi-5-9-2 is not installable

[littlephone]

What's tested

When I try to use the script install.sh to install unity8, it said that qtbase-abi-5-9-2 is not installable. Then I attempt to open the repo site http://repos.ubports.com and find out that multiple apps are depending on such package.

Then I typed in the command:
apt-cache search qtbase-abi
the result is:
libqt5core5a - Qt 5 core module

I think the dependency has changed and now the unity8 should be depending on libqt5core5a instead of qtbase-abi and qtdeclarative-abi for libqt5qml5.

This issues happens in either bionic or xenial as far as I have concerned.

Reference
#17
#19

What's not tested
Running unity8

[mariogrip]

Fixed