TrimSpace Config has no effect on StringSliceFlag

[ayoisaiah]

My urfave/cli version is

v3.3.8

Checklist

• Are you running the latest v3 release? The list of releases is here.
• Did you check the manual for your release? The v3 manual is here
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Describe the bug

Strings arguments to a StringSliceFlag are always trimmed regardless of the TrimSpace configuration

To reproduce

// See flag_test.go

// Existing test
		{
			name:   "StringSliceFlag valid with TrimSpace",
			input:  "foo , bar ",
			output: []string{"foo", "bar"},
			fl:     &StringSliceFlag{Name: "names", Sources: EnvVars("NAMES"), Config: StringConfig{TrimSpace: true}},
		},

// Add a new test with TrimSpace set to false
		{
			name:   "StringSliceFlag valid without TrimSpace",
			input:  "foo , bar ",
			output: []string{"foo ", " bar "},
			fl:     &StringSliceFlag{Name: "names", Sources: EnvVars("NAMES"), Config: StringConfig{TrimSpace: false}},
		},

Observed behavior

Spaces are trimmed regardless:

[]string{"foo", "bar"}

Expected behavior

I expected it to preserve spaces with TrimSpace set to false

 []string{"foo ", " bar "}