Replace deprecated structopt with clap in datafusion-benchmarks (#19492)

## 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The structopt crate is deprecated and has been superseded by clap with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.

Author: Yuvraj-cyborg

Cargo.lock

@@ -40,6 +40,7 @@ mimalloc_extended = ["libmimalloc-sys/extended"]
 
 [dependencies]
 arrow = { workspace = true }
+clap = { version = "4.5.53", features = ["derive"] }
 datafusion = { workspace = true, default-features = true }
 datafusion-common = { workspace = true, default-features = true }
 env_logger = { workspace = true }
@@ -54,7 +55,6 @@ regex.workspace = true
 serde = { version = "1.0.228", features = ["derive"] }
 serde_json = { workspace = true }
 snmalloc-rs = { version = "0.3", optional = true }
-structopt = { version = "0.3", default-features = false }
 tokio = { workspace = true, features = ["rt-multi-thread", "parking_lot"] }
 tokio-util = { version = "0.7.17" }