fixing header and maxEvents for jet reconstruction nightly tests

The edits to test_jet.sh in this MR make the necessary fixes so that nightly ART jobs run successfully. The header has removed the input file because we are reading the file directly from cvmfs nightlies. Also, the maxEvents in the test file may not always be 3000, so -1 is given as a precaution. @tcuhadar

This merge request affects 1 file:

• Reconstruction/Jet/JetValidation/test/test_jet.sh

Adding @goetz as watcher

added JetEtmiss Reconstruction master review-pending-level-1 labels

Trivial changes that are well explained in the description. Ready to approve once CI passes. -- L1

CI Result SUCCESS (hash 9f3b1926)

	Athena	AthSimulation	AthGeneration	AnalysisBase
externals
cmake
make
required tests
optional tests

Full details available on this CI monitor view
Athena: number of compilation errors 0, warnings 0
AthSimulation: number of compilation errors 0, warnings 0
AthGeneration: number of compilation errors 0, warnings 0
AnalysisBase: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-CC7 23423]

added review-approved label and removed review-pending-level-1 label

merged

mentioned in commit 4e508336

added sweep:ignore label