Upgrading apk-tools to remediate CVE-2021-36159
( https://snyk.io/vuln/SNYK-ALPINE314-APKTOOLS-1533752

 )

Fixes #943

Signed-off-by: Dave Hay <david_hay@uk.ibm.com>

Co-authored-by: Yoav Rotem <yoavrotems97@gmail.com>