BREAKING(fs,dotenv): drop Deno v1.x support

[iuioiua]

This PR drops Deno v1.x from being used in CI, or rather it just removes the guarantee that the Standard Library will work with Deno v1.x (even though it does 99% of the time). I think this is reasonable to do now as Deno 2 is LTS.

The title is accurate but may seem more significant than these changes are. This just changes the expected error when insufficient permissions are granted for some operations in @std/fs and @std/dotenv. See Deno.errors.NotCapable.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.17%. Comparing base (f8894da) to head (ebdb7eb).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6624      +/-   ##
==========================================
- Coverage   94.74%   94.17%   -0.57%     
==========================================
  Files         583      580       -3     
  Lines       46478    41419    -5059     
  Branches     6523     6511      -12     
==========================================
- Hits        44036    39008    -5028     
+ Misses       2399     2362      -37     
- Partials       43       49       +6     

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[kt3k]

v1 is still significantly used according to our internal check. (Probably many users are still stuck with v1 because of CLI's breaking changes)

I don't think we are ready to do this change.

cc @bartlomieju @ry

[kt3k]

If we drop v1 CI, we don't what packages work in v1 anymore (any package could randomly break in v1 in the future development)