ulimit defaults add NOFILE (number of open files)

some projects, especially those that use NPM, hit the NOFILE (number of open files) limit during builds

this change sets a working default

the two projects that are known to succeed with this change (and fail without) are:

• https://repo1.dso.mil/dsop/hpe/mldm/haberdashery/-/settings/ci_cd
• https://repo1.dso.mil/dsop/opensource/cassproject/cass/-/settings/ci_cd

trigger run:

https://code-ib-mario.staging.dso.mil/ironbank-tools/tools/trigger/-/jobs/203053