Ivan Cheltsov was supported by the EPSRC Grant Number EP/V054597/1.
The work of V. V. Przyjalkowski was performed at the Steklov International Mathematical Center and supported by the Ministry of Science and Higher Education of the Russian Federation (agreement no. 075-15-2022-265). He is a Young Russian Mathematics award winner and would like to thank its sponsors and jury.
Поступила в редакцию: 21.12.2021 Принята в печать: 18.07.2022