fix(deps): update rust crate graphviz-rust to 0.9

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
graphviz-rust	dependencies	minor	0.6 -> 0.9

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Configuration

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 80.72%. Comparing base (da9dcac) to head (0aecf74).

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #53   +/-   ##
=======================================
  Coverage   80.72%   80.72%           
=======================================
  Files          48       48           
  Lines        6740     6740           
=======================================
  Hits         5441     5441           
  Misses       1299     1299           

Components	Coverage Δ
boomerang	100.00% <ø> (ø)
boomerang_derive	89.10% <ø> (ø)
boomerang_runtime	75.42% <ø> (ø)
boomerang_tinymap	88.17% <ø> (ø)
boomerang_util	20.48% <ø> (ø)