debug-ext sed misusage

[Frozen]

Describe the bug
make debug-ext provides errors on execution. Sonoma 14.6, zsh5.9

To Reproduce
Steps to reproduce the behavior:

harmony % make debug-ext
# update localnet block per epoch to ensure a stable localnet
sed -i 's/localnetBlocksPerEpoch\s*=\s*[0-9]*/localnetBlocksPerEpoch = 64/' internal/configs/sharding/localnet.go
sed: 1: "internal/configs/shardi ...": command i expects \ followed by text
make: *** [debug-ext] Error 1

Expected behavior
A clear and concise description of what you expected to happen.

Screenshots
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Environment (please complete the following information):

harmony % echo $SHELL
/bin/zsh
harmony % /bin/zsh --version
zsh 5.9 (x86_64-apple-darwin23.0)
Sonoma 14.6

Additional context
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