Replace deprecated structopt with clap in datafusion-benchmarks

[Yuvraj-cyborg]

Which issue does this PR close?

Closes - #19482
(Part of #19072 )

Rationale for this change

The structopt crate is deprecated and has been superseded by clap with its derive feature.
This migration:

• Removes a deprecated dependency
• Potentially improves compilation times for the benchmarks crate
• Keeps the codebase up-to-date with modern Rust ecosystem practices

What changes are included in this PR?

• Updated Cargo.toml to use clap = { version = "4.5.53", features = ["derive"] } instead of structopt

• Migrated all benchmark source files to use clap's derive macros:

• #[derive(StructOpt)] → #[derive(Parser/Args/Subcommand)]

• #[structopt(...)] → #[arg(...)] for fields

• #[structopt(...)] → #[command(...)] for struct/enum-level attributes

• StructOpt::from_args() → Parser::parse()

• Removed parse(from_os_str) as PathBuf works natively in clap

• Changed short flag strings to chars ('p' instead of "p")

Are these changes tested?

Yes

Are there any user-facing changes?

No. The CLI interface remains identical - this is a drop-in replacement of the underlying argument parsing library.

[Yuvraj-cyborg]

cc: @alamb @Jefffrey @martin-g @timsaucer