fix(settings): stop using Config.env_prefix for secrets in BaseSettings

[PrettyWood]

Change Summary

We were using the env_prefix for secrets, which doesn't make sense and is very confusing.
Now we just don't

⚠️ ⚠️ Probably good to first be sure we want to go with this option. Feedback welcome on the linked issue ⚠️ ⚠️

Related issue number

closes pydantic/pydantic-settings#30

Checklist

• Unit tests for the changes exist
• Tests pass on CI and coverage remains at 100%
• Documentation reflects the changes where applicable
• changes/<pull request or issue id>-<github username>.md file added describing change
  (see changes/README.md for details)

[codecov]

Codecov Report

Merging #2190 (b6a1c2c) into master (13a5c7d) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master     pydantic/pydantic#2190   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           21        21           
  Lines         4199      4198    -1     
  Branches       854       853    -1     
=========================================
- Hits          4199      4198    -1     

Impacted Files	Coverage Δ
pydantic/env_settings.py	100.00% <100.00%> (ø)

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[samuelcolvin]

I think this is great but we need:

• a prominent !note in the docs explaining this
• a **breaking change:** prefix on the description

[PrettyWood]

Added the "breaking change" mention and a note in the doc

Hope it's clear enough

[samuelcolvin]

Looks good to me, but sadly this has some fairly complicated conflicts.

[samuelcolvin]

Wow this is old 🙈.

@PrettyWood what do you think? V1.10, V2 or close.

[PrettyWood]

I would close as much as possible and avoid a breaking change

[samuelcolvin]

But should we keep this for V2?

[PrettyWood]

the env_prefix for secrets, which doesn't make sense and is very confusing.

I still agree with myself 😄 If we can change this in v2, that will be great! We can keep this open not to forget but if the issue remains open, I don't know it's worth the duplicate. Your call

[samuelcolvin]

Great, keeping it open.

[samuelcolvin]

Closing this, as any new PR would need to be against https://github.com/pydantic/pydantic-settings