Qt 5.14 + 5.15 fixes
Pulling over https://github.com/ubports/ubuntu-ui-toolkit/pull/72 and https://github.com/ubports/ubuntu-ui-toolkit/pull/83
to l-ui-tk on GitLab.
Pulling over https://github.com/ubports/ubuntu-ui-toolkit/pull/72 and https://github.com/ubports/ubuntu-ui-toolkit/pull/83
to l-ui-tk on GitLab.