🐛 Remove creation of extract destination (#3)

https://docs.docker.com/engine/reference/commandline/cp/

Current behaviour:

> DEST_PATH exists and is a directory [...] the source directory is copied into this directory

Desired behaviour:

> DEST_PATH is created as a directory and the contents of the source directory are copied into this directory

src/extract.js

@@ -8,7 +8,6 @@ async function run() {
     const destination = `.extracted-${Date.now()}`;
     const create = `docker cp $(docker create ${image}):/${path} ${destination}`;
 
-    await exec.exec(`mkdir -p ${destination}`);
     await exec.exec(`/bin/bash -c "${create}"`, []);
 
     core.setOutput('destination', destination);