fix(stepper): add missing stepper provider

[yggg]

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• I read and followed the CONTRIBUTING.md guide.
• I read and followed the New Feature Checklist guide.

Short description of what this resolves:

#1669

[codecov]

Codecov Report

Merging #1831 into 3.6.0 will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##            3.6.0    #1831      +/-   ##
==========================================
+ Coverage   82.51%   82.51%   +<.01%     
==========================================
  Files         224      224              
  Lines        7275     7276       +1     
  Branches      600      600              
==========================================
+ Hits         6003     6004       +1     
  Misses       1094     1094              
  Partials      178      178

Impacted Files	Coverage Δ
...work/theme/components/stepper/stepper.component.ts	47.61% <100%> (+0.84%)	⬆️