Replace deprecated "filter" by "where" in registry.nu

[Muttsuri]

nushell deprecated filter in favour of where.
Should be drop in replacement.

Description

After recent update a nushell message:

Warning: nu::parser::deprecated

  × Command deprecated.
    ╭─[/home/muttsuri/.config/nushell/modules/nupm/utils/registry.nu:71:45]
 70 │             # Find all packages matching $package in the registry
 71 │             let pkg_files = $registry.reg | filter $name_matcher
    ·                                             ──────────┬─────────
    ·                                                       ╰── filter was deprecated in 0.105.0 and will be removed in a future release.
 72 │
    ╰────
  help: `where` command can be used instead, as it can now read the predicate closure from a variable

I think in the relevant file nupm already uses a closure to hold the condition, so as far as I can tell no further changes should be required.
Sorry if the PR is lackin in something I'm doing this mid work and I'm very green at this (first PR actually).

[cptpiepmatz]

Yeah, that should be it, thanks!

[cptpiepmatz]

Oh, the CI runs on an old version of nu

[Muttsuri]

Noob question, is it safe to drop my branch?

[fdncred]

yes