[github-action] enhance ncp mode workflow

[Irving-cl]

This PR enhances the ncp_mode github workflow in CI.

A few enhancement is done:

1. Build docker image in the workflow for testing the border routing functionality.
2. Change the usage of ncp_mode script. Use the same parameter style as script/test.
3. Accelerate the workflow by avoiding building unnecessary dependencies: openthread library (in bootstrap), unit test, OTBR web

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 45.92%. Comparing base (2b41187) to head (04fe616).
Report is 846 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2563      +/-   ##
==========================================
- Coverage   55.77%   45.92%   -9.86%     
==========================================
  Files          87      104      +17     
  Lines        6890    12381    +5491     
  Branches        0      903     +903     
==========================================
+ Hits         3843     5686    +1843     
- Misses       3047     6384    +3337     
- Partials        0      311     +311     

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