docs: Update docs about alias storages to match the implementation

[Pijukatel]

Description

• Current implementation does not give alias='default' any special meaning.
• Unnamed default storage should be accessed without mentioning the alias.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.41%. Comparing base (a0b2937) to head (55b1dd8).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1751   +/-   ##
=======================================
  Coverage   92.41%   92.41%           
=======================================
  Files         156      156           
  Lines       10624    10624           
=======================================
  Hits         9818     9818           
  Misses        806      806           

Flag	Coverage Δ
unit	92.41% <ø> (ø)

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[vdusek]

When did we change this?

[Pijukatel]

When did we change this?

#1386 (comment)

[vdusek]

Oh, I see, thanks. So it's __default__ instead of default, right? And you think we should keep this private and not mention it in the docs. That works for me; just ensuring I understand it correctly. Thanks for fixing it.