Update DS CI template to use a single rules:exists glob

What does this MR do and why?

All Dependency Scanning(DS) analyzer jobs ie gemnasium, gemnasium-maven, gemnasium-sbt, are being triggered for users with large projects even if the analyzer is irrelevant to the project. See this comment for full context.

This is because DS uses rules:exists which has a 10k limit check. The 10k checks are counted by the glob path patterns times the number of files in the repo. For projects with many files, the job is triggered if the 10k limit is exceeded.

As each DS job is configured to match multiple glob path patterns in the rules:exists array, this reduces the upper limit of project file size before all jobs are triggered:

• gemnasium has 10 glob path patterns which means project file size upper limit before job runs is 999
• gemnasium-maven has 4 glob path patterns which means project file size upper limit before job runs is 2499
• gemnasium-python has 7 glob path patterns which means project file size upper limit before job runs is 1428

This MR as proposed by @bwill in this comment combines the multiple glob path patterns into a single glob path pattern which significantly increases the upper limit of project file size before all DS jobs are triggered.

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Before	After

Validation of template change

1. I previously created a maven project
2. The pipeline that uses the existing DS ci-template starts both the gemnasium and gemnasium-maven job
3. I started another pipeline with the DS ci-template from this MR and only the gemnasium-maven job is started.

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

1. Create a project