so we don't need pyrcc5, which is not deterministic,
and so we don't need the submodule for the icons
based on electrumsv/electrumsv@bf8802c2eaf0bf75565b5423a95bcb85ec7eb781
When bumping pyinstaller to 3.4, binary sizes had increased drastically.
The main reason seems to be that pyinstaller is pulling in "all" of qt.
based on Electron-Cash/Electron-Cash@4b0996959420dfca3d53f178d86205616d8c568b