Fix non-numeric parameter while generating erlang cookie

[dorbae]

Fix OpenSSL rand command argument validation error

Description

In newer versions of OpenSSL (after commit bd4850df), argument validation for the openssl rand command has become more strict. This can cause errors when invalid argument values (e.g., "32op") are passed.

I tested it on OpenSSL 1.1.1k. In this version, you can see rand: Can't parse "32op" as a number

Related issue and scope

• I opened an issue to propose and discuss this change (#????)

My changes affect the following components

• API
• Controller
• Message Bus (e.g., Kafka)
• Loadbalancer
• Scheduler
• Invoker
• Intrinsic actions (e.g., sequences, conductors)
• Data stores (e.g., CouchDB)
• Tests
• Deployment
• CLI
• General tooling
• Documentation

Types of changes

• Bug fix (generally a non-breaking change which closes an issue).
• Enhancement or new feature (adds new functionality).
• Breaking change (a bug fix or enhancement which changes existing behavior).

Checklist:

• I signed an Apache CLA.
• I reviewed the style guides and followed the recommendations (Travis CI will check :).
• I added tests to cover my changes.
• My changes require further changes to the documentation.
• I updated the documentation where necessary.

[dgrove-oss]

lgtm. Thanks!