fix ERB.new to remove deprecation warnings

[johrstrom]

fix ERB.new to remove deprecation warnings.

The warnings in question are these 2:

/users/PZS0714/johrstrom/ondemand/misc/core/lib/ood_core/job/adapters/kubernetes/batch.rb:242: warning: Passing safe_level with the 2nd argument of ERB.new is deprecated. Do not use it, and specify other arguments as keyword arguments.
/users/PZS0714/johrstrom/ondemand/misc/core/lib/ood_core/job/adapters/kubernetes/batch.rb:242: warning: Passing trim_mode with the 3rd argument of ERB.new is deprecated. Use keyword argument like ERB.new(str, trim_mode: ...) instead.

[Oglopf]

Looks good.