Reproduction repository: https://github.com/AussieGuy0/drools-bug

Summary
When large rule (.drl) files are complied *with* the security manager turned
on in a servlet container (e.g. Tomcat), it causes `AccessControlExceptions`, which causes `NoClassDefFoundErrors`.

Steps
Prereqs: Program is run in servlet context (e.g .war file in tomcat)
1. Turn on security manager
2. Provide policy files through the properties `java.security.policy` and `kie.security.policy`
3. Compile a `.drl` file that has more than `parallelRulesBuildThreshold` (default: 10) rules

Expected Result
Rules are compiled successfully

Actual Result
No class def error

Cause
In `KnowledgeBuilderImpl`, a `ForkJoinPool` is created and used for parallel building.
A `ForkJoinPool` with no `ForkJoinWorkerThreadFactory` specified, it will use a default factory
that provides it's own permissions. These permissions are not sufficient for compiling
drl files in a servlet context.

Potential Fix
A potential fix is to allow the user to provide their own `ForkJoinWorkerThreadFactory` as a
configuration option for drools.