Definition of trivial contributions

As part of setting up a project for cake-contrib I was reading through the guidelines for [Cake Contributions](https://cakebuild.net/community/contributing/contribution-guidelines). The section about [definition of trivial contributions](https://cakebuild.net/community/contributing/contribution-guidelines#definition-of-trivial-contributions) does not explain why trivial contributions needs to be defined. After reading it I am not sure why it matters if a contribution is trivial or not. Perhaps this section can be improved to make it more clear.

Open the Cake Contributions guidelines and read the “definition of trivial contributions” section, especially the linked anchor in the issue. Clarify why distinguishing trivial contributions matters, using the surrounding guidelines for context; it is done when a reader understands the purpose of the definition without further explanation.

Written by the indexing model from the issue text.