Update setup script to create branch and markdown header with correct date

[sreeram-venkitesh]

script.sh can be used to create the branch and the issue template easily every week. The date command uses -sun to get the correct date for each week's issue.

CC: @jberkus @fykaa

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[fykaa]

This script looks good, I just think date -v is BSD specific, so it may not work on Linux

and ig replacing hardcoded dates in sed with variables could make future edits easier

[sreeram-venkitesh]

Thanks for catching that! I've pushed some changes. I tried running the date -d command in a linux box but didn't clone lwkd and try out the entire script. Please take a look!

[jberkus]

Sed commands still fail for me on Linux/BASH:

sed: can't read s/2025-01-22/2025-02-25/g: No such file or directory
sed: can't read s/Month DD/February 23/g: No such file or directory

[sreeram-venkitesh]

Finally got around to fixing this. @jberkus Can you try now?