fix: truncate blog (#1730)

apps/docs/blog/2024-06-29-impact-metrics-rf4-deep-dive/index.md

@@ -12,6 +12,8 @@ As discussed in our companion post, [Impact Metrics for Optimism Retro Funding 4
 
 This post is a deeper dive on the work we did at Open Source Observer to help organize data about projects and prepare Optimism badgeholders for voting.
 
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 ## Where the metrics come from
 
 We built a first-of-its-kind data pipeline for the Superchain: not only the data but also all source code, query logic, and underlying infrastructure is publicly available for use. We aren’t aware of any other fully open data pipelines of this size or complexity built this way.
@@ -114,8 +116,6 @@ We're excited to see how this type of model evolves and is extended for future u
 
 ## Developing the impact metrics
 
-### Principles
-
 The following design principles guide the development and evolution of [impact metrics](https://docs.opensource.observer/docs/how-oso-works/impact-metrics/#principles):
 
 - Verifiability: Metrics should be based on public data that can be independently verified. They should not rely on proprietary data sources or private APIs.