Qt Options 对话框中存在无法删除的Qt版本(There is an undeletable Qt version in Qt Options Dialog)

在Add New Qt Version时将Version name设置为Qt5.12.4\msvc2017后点击OK，然后出现这样的问题。Qt路径没有问题，问题在于写入注册表时不能把Qt5.12.4\msvc2017整体作为键名，实际上是创建了名为Qt5.12.4的主键和msvc2017的子键，子键的InstallDir值为Qt路径，而主键没有名称为InstallDir的值。

If you set "Version name" to "Qt5.12.4\msvc2017" and click OK when adding version in "Add New Qt Version" dialog, then the bug occurs. The path of Qt is correct and the problem is  you can't write "Qt5.12.4\msvc2017" as key name into windows registry. In fact, when you do this, you create a main key named "Qt5.12.4" and a subkey named "msvc2017". The value of "InstallDir" of the subkey is the path of Qt and the main key doesn't have the value named "InstallDir".