chore: build the flate2 crate as optimized in the dev profile

flate2 1.0.28 built unoptimized is significantly slower than before
an unsafe unsoundness was fixed. This unnecessarily slows down some
of our tests which use `flate2` during test setup.

For more info please check rust-lang/flate2-rs#395

This change makes sure that `flate2` is optimized even for a `dev` build.

Cargo.toml

@@ -31,6 +31,9 @@ inherits = "release"
 codegen-units = 1
 lto = true
 
+[profile.dev.package.flate2]
+opt-level = 3
+
 [workspace.package]
 version = "0.11.0"
 edition = "2021"