Fix File.open Ruby 3.2 regression in FileSystem::Uniquefile

[JonasVerhofste]

Short description

Ruby 3.2 changed the method call of File.open() such that it always requires perm as an argument if you want to pass other opts. It also started requiring opts to be splatted, instead of passed as a hash.

I didn't go through the whole codebase to see if there are other places where this regression (can) happen(s). I just ran into this one when working on an older internal provider that uses Puppet::FileSystem::Uniquefile.new() directly (not through the open_tmp() method).

Old method definition:

open(filename, mode="r" [, opt]) → file
open(filename [, mode [, perm]] [, opt]) → file
open(filename, mode="r" [, opt]) {|file| block } → obj
open(filename [, mode [, perm]] [, opt]) {|file| block } → obj

New method definition:

open(path, mode = 'r', perm = 0666, **opts) → file
open(path, mode = 'r', perm = 0666, **opts) {|f| ... } → object

Checklist

I have:

• read the CONTRIBUTING.md document
• read and accepted the Developer Certificate of Origin document and added a Signed-off-by annotation to each of my commits
• read and accepted the AI Policy document and added Generated-by or Assisted-by annotations to each of my commits created with the help of an AI agent
• tested this code
• added or modified regression test(s)
• added or modified unit test(s)