feat: support external mode

[yndu13]

No description provided.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 88.09524% with 35 lines in your changes missing coverage. Please review.
✅ Project coverage is 94.87%. Comparing base (0bfdeb4) to head (6e37f35).

Files with missing lines	Patch %	Lines
alibabacloud_credentials/provider/external.py	82.00%	18 Missing ⚠️
alibabacloud_credentials/provider/cli_profile.py	72.88%	16 Missing ⚠️
tests/provider/test_external.py	98.82%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #83      +/-   ##
==========================================
- Coverage   95.11%   94.87%   -0.25%     
==========================================
  Files          48       50       +2     
  Lines        7315     7609     +294     
==========================================
+ Hits         6958     7219     +261     
- Misses        357      390      +33     

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