Ensure evaluation pipeline config load resets groovy binding before the load

[andrew-m-leonard]

Ensure evaluation pipeline config load resets groovy binding before the load, so any old values are not picked up.
Same fix as cedc501
Also fixed typo in jdk17u schedule.

Fixes: #789

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[sxa]

I don't know enough about the way these pipelines work to give a full code review based on the description, but this superficially sounds reasonable and if you believe it fixes the pipeline triggers then it shouldn't make things any worse, so I'm approving :-)