[Do Not Merge]luis and qnamaker build support to write out empty crosstrained recognizer

[feich-ms]

fix composer issue microsoft/botbuilder-dotnet#4144

[codecov-commenter]

Codecov Report

Merging #870 into master will decrease coverage by 0.22%.
The diff coverage is 7.95%.

@@            Coverage Diff             @@
##           master     #870      +/-   ##
==========================================
- Coverage   58.24%   58.02%   -0.23%     
==========================================
  Files         218      217       -1     
  Lines       15622    15497     -125     
  Branches     2089     2087       -2     
==========================================
- Hits         9099     8992     -107     
+ Misses       5954     5945       -9     
+ Partials      569      560       -9     

Impacted Files	Coverage Δ
packages/lu/src/parser/lu/luMerger.js	76.34% <0.00%> (ø)
packages/lu/src/parser/lubuild/builder.ts	12.44% <0.00%> (-0.37%)	⬇️
packages/lu/src/parser/lubuild/core.ts	16.08% <0.00%> (-0.22%)	⬇️
packages/lu/src/parser/qnabuild/builder.ts	22.85% <0.00%> (-0.58%)	⬇️
packages/lu/src/parser/qnabuild/core.ts	21.73% <0.00%> (-0.59%)	⬇️
packages/lu/src/parser/utils/enums/CLI-errors.js	100.00% <ø> (ø)
packages/luis/src/commands/luis/build.ts	79.78% <100.00%> (-0.22%)	⬇️
packages/qnamaker/src/commands/qnamaker/build.ts	76.53% <100.00%> (-0.32%)	⬇️
packages/lg/src/commands/lg/index.ts	66.66% <0.00%> (-16.67%)	⬇️
packages/qnamaker/src/commands/qnamaker/index.ts	66.66% <0.00%> (-16.67%)	⬇️
... and 34 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 3be1143...132f242. Read the comment docs.

[feich-ms]

close this one since it is merged into PR #889 which depends on this one.