BulletInterface: Unit test for contact monitoring

[coveralls]

Pull Request Test Coverage Report for Build 9083262902

Details

• 18 of 18 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.8%) to 89.781%

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Totals
Change from base Build 9045323878:	0.8%
Covered Lines:	1845
Relevant Lines:	2055

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💛 - Coveralls