Fix concurrency issues (#142)

* Fix the OS FD error

* Cache the compiler versions

* Allow for auto display impl in declare wrapper type macro

* Better logging and fix concurrency issues

* Fix tests

* Format

* Make the code even more concurrent

crates/compiler/tests/lib.rs

@@ -11,7 +11,6 @@ async fn contracts_can_be_compiled_with_solc() {
     let compiler_path = Solc::get_compiler_executable(&args, Version::new(0, 8, 30))
         .await
         .unwrap();
-    println!("About to assert");
 
     // Act
     let output = Compiler::<Solc>::new()