[Instrumentation.SqlClient] Implements database metric db.client.operation.duration (part 2/netfx)

[matt-hensley]

Changes

Implements proposed db.client.operation.duration metric for SqlClient.

Adds implementation for .NET Framework.

Merge requirement checklist

• CONTRIBUTING guidelines followed (license requirements, nullable enabled, static analysis, etc.)
• Unit tests added/updated
• Appropriate CHANGELOG.md files updated for non-trivial changes
• Changes in public API reviewed (if applicable)

[codecov]

Codecov Report

Attention: Patch coverage is 88.33333% with 7 lines in your changes missing coverage. Please review.

Project coverage is 89.77%. Comparing base (71655ce) to head (4a925c4).
Report is 596 commits behind head on main.

Files with missing lines	Patch %	Lines
...ent/Implementation/SqlEventSourceListener.netfx.cs	82.50%	7 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #2311       +/-   ##
===========================================
+ Coverage   73.91%   89.77%   +15.85%     
===========================================
  Files         267        9      -258     
  Lines        9615      440     -9175     
===========================================
- Hits         7107      395     -6712     
+ Misses       2508       45     -2463     

Flag	Coverage Δ
unittests-Instrumentation.SqlClient	89.77% <88.33%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...qlClient/Implementation/SqlActivitySourceHelper.cs	100.00% <100.00%> (ø)
...ient/Implementation/SqlClientDiagnosticListener.cs	89.06% <100.00%> (ø)
...ent/Implementation/SqlEventSourceListener.netfx.cs	79.20% <82.50%> (ø)

... and 270 files with indirect coverage changes