Improve error behaviour for tracking core plugin calls

[alexbridge]

Description

Improve error behaviour for tracking core plugin calls

Type of change

Please add an "x" into the option that is relevant:

• [ ] Bug Fix 🐛 (non-breaking change which fixes an issue)
• [ ] New Feature 🚀 (non-breaking change which adds functionality)
• [ ] Breaking Change 💥 (fix or feature that would cause existing functionality to not work as expected)
• [ ] Polish 💅 (Just some cleanups)
• [ ] Docs 📝 (Changes in the documentations)
• Internal 🏠 Only relates to internal processes.

[coveralls]

Pull Request Test Coverage Report for Build 2100

• 2 of 20 (10.0%) changed or added relevant lines in 4 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.06%) to 47.073%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
libraries/tracking/subscriptions/setup.js	0	4	0.0%
libraries/common/subscriptions/error.js	0	7	0.0%
libraries/tracking-core/core/Core.js	0	7	0.0%

Files with Coverage Reduction	New Missed Lines	%
libraries/common/subscriptions/error.js	1	0.0%

Totals
Change from base Build 2099:	-0.06%
Covered Lines:	5066
Relevant Lines:	10100

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💛 - Coveralls