Strip periods, spaces for batch file filtering on Windows

[GeopJr]

fix: #15560

As discussed in the linked issue, the options on the table are either GetFullPathNameW or stripping trailing . and . This PR does the latter.

Here's a benchmark between them, the difference seems insignificant, considering executing is going to take longer. Stripping is faster anyway.

require "benchmark"

File.write("foo.bat", "calc.exe") unless File.exists?("foo.bat")
COMMAND = "foo.bat . .  .. #{ARGV[0]? || ""}"

Benchmark.ips do |x|
  x.report("GetFullPathNameW") do
    wstr_path = Crystal::System.to_wstr(COMMAND)
    Crystal::System.retry_wstr_buffer do |buffer, small_buf|
      len = LibC.GetFullPathNameW(wstr_path, buffer.size, buffer, nil)
      if 0 < len < buffer.size
        break String.from_utf16(buffer[0, len])
      elsif small_buf && len > 0
        next len
      else
        raise ::File::Error.from_winerror("Error resolving real path", file: COMMAND)
      end
    end
  end

  x.report("rstrip") do
    COMMAND.rstrip(". ")
  end
end

# GetFullPathNameW 967.44k (  1.03µs) (± 2.75%)   112B/op   2.75× slower
#           rstrip   2.66M (376.29ns) (± 1.42%)  32.0B/op        fastest

Draft until the CI finishes because I haven't actually tested on Windows.

_{I don't like the commit name that much but it's the most descriptive one I could come up with.}