Merge pull request github#55 from github/remove-metric

Remove mention of problematic metric that will not be implemented

Author: zkoppert

docs/open-source-health-metrics.md

@@ -48,7 +48,6 @@ The Repository object in the GraphQL API is the primary location for metrics whi
 
 - **LastContributionDate** - The most recent date there was _any of_ the following activity: a commit to a repository’s default branch, opening an issue or discussion, answering a discussion, proposing a pull request, or submitting a pull request review. This is a good single-number metric to find projects that may be unmaintained or in need of archiving.
 - **CommitCount** - A monotonically increasing count of the total number of commits pushed to the default branch of the repository. Tracking the change in this over time will give a sense of the overall activity in the repository.
-- **IssueCommentCount** - Similar to CommitCount, this is a monotonically increasing count of the total number of comments on issues in the repository.
 
 ### More useful metrics