Drop outdated touch -d example (nushell#13631)

Fixes nushell#8723

# Description

The example was showing the flag that no longer exists.

# User-Facing Changes

Help no longer shows the example with `-d` flag.

# Tests + Formatting

I trust in CI.

# After Submitting

Nothing.

crates/nu-command/src/filesystem/touch.rs

@@ -179,11 +179,6 @@ impl Command for Touch {
                 example: "touch -m fixture.json",
                 result: None,
             },
-            Example {
-                description: "Changes the last modified time of files a, b and c to a date",
-                example: r#"touch -m -d "yesterday" a b c"#,
-                result: None,
-            },
             Example {
                 description: r#"Changes the last modified time of file d and e to "fixture.json"'s last modified time"#,
                 example: r#"touch -m -r fixture.json d e"#,