perf(sme): use featureFlagManager instead of global function

[SLdragon]

#11776 (comment)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.45%. Comparing base (8b61126) to head (5712f72).

Additional details and impacted files

@@            Coverage Diff             @@
##              dev   #11785      +/-   ##
==========================================
- Coverage   88.45%   88.45%   -0.01%     
==========================================
  Files         530      530              
  Lines       32484    32480       -4     
  Branches     6385     6337      -48     
==========================================
- Hits        28733    28729       -4     
  Misses       1817     1817              
  Partials     1934     1934              

Files	Coverage Δ
packages/fx-core/src/common/featureFlags.ts	96.22% <ø> (-0.27%)	⬇️
...ackages/fx-core/src/component/coordinator/index.ts	87.57% <100.00%> (ø)
...core/src/component/driver/oauth/utility/utility.ts	97.56% <100.00%> (ø)
...src/component/generator/copilotPlugin/generator.ts	89.75% <100.00%> (ø)
...re/src/component/generator/copilotPlugin/helper.ts	93.39% <100.00%> (ø)
packages/fx-core/src/question/create.ts	93.43% <ø> (ø)