Fix connections sometimes failing to gen on cityless overmaps #90212

Job	Run time
skip-duplicates-code	5s
matrix-variables	1s
skip-duplicates-data	5s
Basic Build and Test (Clang 10, Ubuntu, Curses)	39m 27s
Clang 14, macOS 12, Tiles, Sound, x64 and arm64 Universal Binary	1h 34m 13s
GCC 9, Curses, LTO	53m 31s
Clang 12, Ubuntu, Tiles, ASan	2h 5m 1s
GCC 11, Ubuntu, Curses, ASan	2h 10m 15s
GCC 12, Ubuntu cross-compile to MinGW-Win64, Tiles, Sound	1h 7m 16s
GCC 9, Ubuntu, Tiles, Sound, CMake	22m 41s
emscripten	0s
	8h 52m 35s

Provide feedback