docs(adapters): adds docs to collateral adapter

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Pull Request Test Coverage Report for Build 5604993118

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 85.269%

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Totals
Change from base Build 5604758319:	0.0%
Covered Lines:	984
Relevant Lines:	1154

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💛 - Coveralls

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