fix(instrumentation-express): Finish spans after execution

[onurtemizkan]

Which problem is this PR solving?

Resolves: #2442

• TBD

Short description of the changes

• TBD

[codecov]

Codecov Report

Attention: Patch coverage is 60.00000% with 4 lines in your changes missing coverage. Please review.

Project coverage is 90.74%. Comparing base (21e1331) to head (c60e4f7).

Files with missing lines	Patch %	Lines
...try-instrumentation-express/src/instrumentation.ts	60.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2603      +/-   ##
==========================================
- Coverage   90.78%   90.74%   -0.05%     
==========================================
  Files         169      169              
  Lines        8055     8057       +2     
  Branches     1643     1642       -1     
==========================================
- Hits         7313     7311       -2     
- Misses        742      746       +4     

Files with missing lines	Coverage Δ
...try-instrumentation-express/src/instrumentation.ts	95.80% <60.00%> (-2.78%)	⬇️

[github-actions]

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