Revisit if halving of `--max-memory` value is appropriate

[yousefmoazzam]

The code comment suggests that the halving is done to account for needing to hold both inputs and outputs of a section in memory:

httomo/httomo/cli.py

Lines 425 to 426 in 5dbdde1

	# we use half the memory for blocks since we typically have inputs/output
	memory_limit = transform_limit_str_to_bytes(max_memory) // 2

However, the function calculating the backing to the dataset store is accounting for the size of both the input and output chunks. Meaning, is there a need to halve the --max-memory value if both inputs and outputs are already being accounted for?