Set zstd compression level to 1 as it offers fastest compression with…

… small size tradeoff. (solana-labs#2729)

Get faster compression level --fast=4

As per https://github.com/facebook/zstd/tree/dev?tab=readme-ov-file#benchmarks
Level=4 offers faster compression 710MB/s vs. 670 MB/s

runtime/src/snapshot_utils.rs

@@ -1083,8 +1083,9 @@ fn archive_snapshot(
                 encoder.finish().map_err(E::FinishEncoder)?;
             }
             ArchiveFormat::TarZstd => {
+                // Compression level of 1 is optimized for speed.
                 let mut encoder =
-                    zstd::stream::Encoder::new(archive_file, 0).map_err(E::CreateEncoder)?;
+                    zstd::stream::Encoder::new(archive_file, 1).map_err(E::CreateEncoder)?;
                 do_archive_files(&mut encoder)?;
                 encoder.finish().map_err(E::FinishEncoder)?;
             }