Separate out emscripten and non emscripten builds into separate workfows

[mcbarton]

Description

Please include a summary of changes, motivation and context for this PR.

This PR will separate the emscripten and non emscripten builds into separate workflows, to make them easier to maintain and update.

Fixes # (issue)

Type of change

Please tick all options which are relevant.

• Bug fix
• New feature
• Requires documentation updates

Testing

Please describe the test(s) that you added and ran to verify your changes.

Checklist

• I have read the contribution guide recently

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 70.87%. Comparing base (cb640db) to head (5c5947f).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #402      +/-   ##
==========================================
+ Coverage   70.84%   70.87%   +0.03%     
==========================================
  Files           9        9              
  Lines        3529     3533       +4     
==========================================
+ Hits         2500     2504       +4     
  Misses       1029     1029              

see 1 file with indirect coverage changes

see 1 file with indirect coverage changes

[vgvassilev]

LGTM!