docs(instrumentation-router): correct import statement

[Netail]

Which problem is this PR solving?

• Router instrumentation import in the documentation

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.86%. Comparing base (8070c7f) to head (672011a).
Report is 1 commits behind head on main.

Additional details and impacted files

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  Coverage   90.86%   90.86%           
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  Files         161      161           
  Lines        7858     7858           
  Branches     1612     1612           
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  Hits         7140     7140           
  Misses        718      718           

[pichlermarc]

thanks 👍