Adding allowed error to MadGraphControl

This error came up in testing, as diagnosed in AGENE-1962

It is associated with ghost script, which really has no impact at all on MadGraph running in production (it has to do with writing images for convenience for local users). This ensures that the job continues happily past the error.

WARNING: big files (>100K) are found in the changeset

116K in file Generators/MadGraphControl/python/MadGraphUtils.py

This merge request affects 1 package:

• Generators/MadGraphControl

This merge request affects 1 file:

• Generators/MadGraphControl/python/MadGraphUtils.py

Adding @zmarshal as watcher

added Generators master review-pending-level-1 labels

CI Result SUCCESS (hash 25d25d60)

	Athena	AthSimulation	AthGeneration	AnalysisBase	AthAnalysis
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
AthAnalysis: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-CC7 29767]

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

merged

mentioned in commit a7679fcd

added sweep:ignore label