Syntax & Style Fixes

[NeoByteXx]

1. Regex Fix in nix_bump_pr_changes.py Old: r"'github:([^/]+/[^/]+)/([^']+)" New: r"'github:([^/]+/[^/]+)/([^']+)" Why? Removed unnecessary backslashes for cleaner regex.
2. Error Message Improvement in Shell Script Old: echo "Unknown option $1" New: echo "Unknown option: $1" Why? Added a colon for better readability.
3. Shell Syntax Cleanup Old: echo "${1}"; exit 1; New: echo "$1"; exit 1 Why? Removed redundant curly braces for cleaner syntax.

[CLAassistant]

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