Use LibLakimia8 for online quotes

LibAlkimia 8 added support for online quotes and we should migrate KMyMoney to use it instead its own custom code.

There is a master-alkimia-alkonlinequote branch with initial migration done. According to TODOs in the commit message, a support for CSVImport and IdentifyBy is required (see commit diff for details).

LibAlkimia also relies on using KDELibs4Support, which is an issue in itself, given how KMM is the last KDE app requiring that support lib and should be made obsolete.

Some relevant links:

Outstanding issues in libalkimia itself: https://bugs.kde.org/buglist.cgi?component=General&list_id=1749102&product=libalkimia&resolution=---
Discussion behind original proposal and implementation: https://bugs.kde.org/show_bug.cgi?id=403029

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