lower number of retries if there is an exception

[davidblasby]

@josegar74 suggested changing (lowering) the number of retries if there is an exception.

I've moved it down to 1.

[CLAassistant]

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[davidblasby]

@juanluisrp - I think there is something wrong with the docker container building. It builds fine locally (mvn clean install and mvn --batch-mode --update-snapshots verify, mvn -B com.github.ferstl:depgraph-maven-plugin:4.0.2:aggregate -DgraphFormat=json -DoutputDirectory=target -DoutputFileName=aggregate-depgraph.json etc...),

There seem to be;

1. mvn errors (building dependency trees - 403)
2. docker creation errors.