Fix es unzip

[LeeDr]

This is a fix for what I believe to be an Elasticsearch change which breaks our scripts for running a snapshot of Elasticsearch on Windows.

I think Elasticsearch changed to no longer create the /logs/ directory on startup if it doesn't already exist. They shouldn't have to create the /logs/ dir because it's included in the zip and tar.gz archives and/or created by installing the packages.
Our decompress.js wasn't creating empty folders when it unzipped elasticsearch and then elasticsearch wouldn't start.

This change adds mkdir to fix it.

This fixes both yarn es snapshot and node scripts/functional_tests_server commands which would previously fail (at least on Windows).

Part of my output when it fails;

 info  Starting
   │ debg  bin/elasticsearch.bat
   │ info  [0.002s][error][logging] Error opening log file 'logs/gc.log': No such file or directory
   │       Initialization of output 'file=logs/gc.log' using options 'filecount=32,filesize=64m' failed.
   │ERROR  Java HotSpot(TM) 64-Bit Server VM warning: Option UseConcMarkSweepGC was deprecated in version 9.0 and will likely be removed in a future release.
   │       Invalid -Xlog option '-Xlog:gc*,gc+age=trace,safepoint:file=logs/gc.log:utctime,pid,tags:filecount=32,filesize=64m'
   │       Error: Could not create the Java Virtual Machine.
   │       Error: A fatal exception has occurred. Program will exit.

[elasticmachine]

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