[BUILD] Fix elasticsearch exporter json compatibility

[dbarker]

Fixes #3312

The system package of nlohmann_json is version 3.10.5 on Ubuntu 22.04.

Changes

• Add a template specialization of the json_assign_visitor to handle nostd::span attribute values.
• Switch one runner that builds the elastic search exporter (runs ./ci/do_ci.sh cmake.test) to Ubuntu 22.04 and CXX_STANDARD=17

For significant contributions please make sure you have completed the following items:

• CHANGELOG.md updated for non-trivial changes
• Unit tests have been added
• Changes in public API reviewed

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.52%. Comparing base (2c9b68f) to head (8309565).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3313      +/-   ##
==========================================
+ Coverage   89.50%   89.52%   +0.02%     
==========================================
  Files         210      210              
  Lines        6522     6522              
==========================================
+ Hits         5837     5838       +1     
+ Misses        685      684       -1     

see 1 file with indirect coverage changes

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[marcalff]

LGTM, thanks for the fix.

[owent]

LGTM, thanks.