Exclude company's own projects filter

I think it would be pertinent to include a filter that excludes contributions to the company's own open source projects.
As much as I enjoy seeing the numbers I feel like it would be amazing to see which companies contribute _outside_ of their own circle of influence the most, this could shift the rankings somewhat and showcase a bit more of the open source community on the top lists.

Throwing this out there as an idea, absolutely understand if this is not relevant to this project but maybe something worth thinking about!

Start by reading the repository's existing ranking and filtering entry points to determine how projects are associated with companies. Define how a company's own open-source projects would be identified and how the exclusion should affect the rankings, then add coverage for the filter's expected results.

Written by the indexing model from the issue text.