Fix `cluster_manager` script (#2940) #3

Job	Run time
get-matrices	8s
get-containers	0s
lint	1m 25s
test-csharp-container	0s
test-csharp (8.0, valkey, 8.0, always, ubuntu, linux, ubuntu-latest, x64, x86_64-unknown-linux-gn...	4m 47s
test-csharp (8.0, redis, 6.2, always, ubuntu, linux, ubuntu-latest, x64, x86_64-unknown-linux-gnu...	4m 21s
	10m 41s

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