[ENG-12793][eas-cli] make eas login and eas whoami behave more clearly when one is authenticated using EXPO_TOKEN

[szdziedzic]

Why

Using EXPO_TOKEN seems confusing to people.

#2460

How

When using the eas whoami command signal that a user is authenticated by using EXPO_TOKEN. It seems like people sometimes tend to forget that they have EXPO_TOKEN set, then they log in as a different account but eas whoami still returns the same value because they are authed using EXPO_TOKEN and it seems to be confusing.

Warn people when running eas login with the EXPO_TOKEN set that this is not necessary.

Test Plan

Test manually

eas whoami after and before

eas login

[github-actions]

Size Change: -455 B (0%)

Total Size: 52 MB

Filename	Size	Change
./packages/eas-cli/dist/eas-linux-x64.tar.gz	52 MB	-455 B (0%)

_{compressed-size-action}

[codecov]

Codecov Report

Attention: Patch coverage is 25.00000% with 12 lines in your changes missing coverage. Please review.

Project coverage is 53.41%. Comparing base (17ecdb2) to head (fd2b914).

Files	Patch %	Lines
packages/eas-cli/src/commands/account/login.ts	33.34%	8 Missing ⚠️
packages/eas-cli/src/commands/account/view.ts	0.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2461      +/-   ##
==========================================
- Coverage   53.43%   53.41%   -0.02%     
==========================================
  Files         530      530              
  Lines       19564    19577      +13     
  Branches     3979     3984       +5     
==========================================
+ Hits        10453    10456       +3     
- Misses       9089     9099      +10     
  Partials       22       22              

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[wschurman]

IMO we should just throw an error when eas login is run when the EXPO_TOKEN is set. Maybe say something like: "EXPO_TOKEN is set in your environment, and is being used for all EAS authentication. To use username/password authentication, unset EXPO_TOKEN in your environment and re-run the command.".

[linear]

ENG-12793 Make sure that if one is using `EXPO_TOKEN` the `eas login` command indicate that they are already authed using the token

[wschurman]

One wording change, otherwise lgtm.

[github-actions]

✅ Thank you for adding the changelog entry!