test(region-provider): add extensive unit tests for region-provider

[trivikr]

Issue #, if available:
Refactored while investigating Retry Configuration task (internal JS-1813)

Description of changes:
add unit tests for region-provider

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[codecov-commenter]

Codecov Report

Merging #1280 into master will decrease coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #1280      +/-   ##
==========================================
- Coverage   73.04%   73.04%   -0.01%     
==========================================
  Files         287      287              
  Lines       12730    12729       -1     
  Branches     2922     2922              
==========================================
- Hits         9299     9298       -1     
  Misses       3431     3431              

Impacted Files	Coverage Δ
packages/region-provider/src/defaultProvider.ts	100.00% <100.00%> (ø)
packages/region-provider/src/fromEnv.ts	100.00% <100.00%> (ø)
...kages/region-provider/src/fromSharedConfigFiles.ts	100.00% <100.00%> (ø)

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[alexforsyth]

LGTM!

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This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs and link to relevant comments in this thread.

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs and link to relevant comments in this thread.