remove kpi folder structure and simplify it

Author: nidhi-singh02

apps/developer-hub/content/docs/metrics/kpi/index.mdx renamed to apps/developer-hub/content/docs/metrics/kpi.mdx

@@ -3,13 +3,17 @@ title: Pyth Network KPI
 description: Monthly informative data points on the Pyth network, its growth, and performance metrics.
 ---
 
-<Callout variant="info" header="Pyth Network KPI " >
-For the latest KPI dashboard, please visit [https://kpi.pyth.network/](https://kpi.pyth.network/).
+<Callout variant="info" header="Pyth Network KPI ">
+  For the latest KPI dashboard, please visit
+  [https://kpi.pyth.network/](https://kpi.pyth.network/).
 </Callout>
-Every month, the Pyth contributors collect informative data points on the network, its growth, as well as its performance.
+Every month, the Pyth contributors collect informative data points on the
+network, its growth, as well as its performance.
 
 <Callout variant="warning" header="Disclaimer">
-All figures mentioned are just rough estimations. Due to Pyth's permissionless nature, any apps can use the Pyth price feeds without talking to the Pyth contributors. This will exclude them from the calculations.
+  All figures mentioned are just rough estimations. Due to Pyth's permissionless
+  nature, any apps can use the Pyth price feeds without talking to the Pyth
+  contributors. This will exclude them from the calculations.
 </Callout>
 
 - **Data Publishers**