refactor: prettier code in igraphmodule_Graph_community_edge_betweenness #1800

Job	Run time
Build wheels on Linux (aarch64/musllinux)	6m 56s
Build wheels on Linux (aarch64/manylinux)	17m 0s
Build wheels for WebAssembly	6m 41s
Build wheels on Linux (i686)	20m 27s
Build wheels on Linux (x86_64)	25m 33s
Build wheels on macOS (x86_64)	10m 8s
Build wheels on Windows (ARM64)	16m 59s
Build wheels on Windows (Win32)	8m 26s
Build wheels on macOS (arm64)	9m 50s
Build sdist and test extra dependencies	2m 51s
Build wheels on Windows (x64)	34m 27s
Build with sanitizers for debugging purposes	3m 18s
	2h 42m 36s

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