Update Ghostscript version to 9.54.0

[mattiloh]

Hi @zappan! First: Thanks for sharing these scripts to create Ghostscript Lambda Layers. It's very handy! But it uses an old version of Ghostscript (9.27) that contains a critical security vulnerability. This vulnerability is actively exploited in the wild since almost ~2 years: https://nvd.nist.gov/vuln/detail/CVE-2019-10216

In the case of this layer, It allows attackers to completely compromise the Lambda container by uploading EPS files containing malicious scripts.

Please update the related Lambda Layer at AWS Serverless Application Repository, so at least new deployments aren't affected by this flaw anymore.

All credits go to @jensvoid who found and reported this vulnerability in a service using this Lamdba Layer.

[marcfalk]

Agreed ✌️ Would be cool to have these layers updated. Thanks for putting them online in the first place 👍