[deps] Update Rust crate syn to v3.0.6

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
syn	workspace.dependencies	patch	3.0.4 → 3.0.6

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Release Notes

dtolnay/syn (syn)

v3.0.6

Compare Source

• Fix parsing interpolated lifetime at statement start (#​2082)

v3.0.5

Compare Source

• Report correct span for lex errors from LitStr::parse_with (#​2080, thanks @​sunshowers)

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 72.61%. Comparing base (5f4406a) to head (736f95c).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #5278   +/-   ##
=======================================
  Coverage   72.61%   72.61%           
=======================================
  Files         339      339           
  Lines       18315    18315           
=======================================
  Hits        13298    13298           
  Misses       5017     5017           

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