Update dependency shfmt to v3.9.0

[renovate]

This PR contains the following updates:

Package	Update	Change
shfmt	minor	3.8.0 -> 3.9.0

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Release Notes

mvdan/sh (shfmt)

v3.9.0

Compare Source

This release drops support for Go 1.21 and includes many fixes.

• cmd/shfmt
  • Switch the diff implementation to remove one dependency
• syntax
  • Protect against overflows in position offset integers
• interp
  • Use os.Pipe for stdin to prevent draining by subprocesses - #​1085
  • Support cancelling reads in builtins when stdin is a file - #​1066
  • Support the nocaseglob bash option - #​1073
  • Support the Bash 5.2 @k parameter expansion operator
  • Support the test -O and test -G operators on non-Windows - #​1080
  • Support the read -s builtin flag - #​1063
• expand
  • Add support for case insensitive globbing - #​1073
  • Don't panic when pattern words are nil - #​1076

A special thanks to @​theclapp for their contributors to this release!

Consider becoming a sponsor if you benefit from the work that went into this release!

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