[#65] Avoid collision in doc item positions

Description

Problem: I defined ManagedLedger's DRequireRole with the same position as in on of our private repos, and actually quite meaninglessly (other doc items for ManagedLedger use different numbering).

Solution: change position to one similar to one near it but slightly less.

Related issue(s)

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• Tests (see short guidelines)

  • If I added new functionality, I added tests covering it.
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    • README
    • Haddock
    • docs/
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