fix: correct unused footnote key 7 reference link in tree cover and forests user manual

Author: MatMatt

DOCS/products/Product_User_Manual_-_Tree_Cover_and_Forests_2018-present.qmd

@@ -603,7 +603,7 @@ PROJCS["ETRS89-extended / LAEA Europe",
 
 ## Spatial resolution
 
-The native spatial resolution of the Tree Cover & Forests products DLT, TCD and FTY is 10 metres and linked to the highest resolution of Sentinel-2 (red, blue, green and near-infrared bands) as the primary input data source. For products at 20 metres and 100 metres, aggregation rules are defined in the ATBD [7]. The spatial resolution should, however, not be confused with the size and location-precision of the elements that can be represented in the maps. The latter is limited by certain factors that are intrinsic to the available input data:
+The native spatial resolution of the Tree Cover & Forests products DLT, TCD and FTY is 10 metres and linked to the highest resolution of Sentinel-2 (red, blue, green and near-infrared bands) as the primary input data source. For products at 20 metres and 100 metres, aggregation rules are defined in the ATBD [^7]. The spatial resolution should, however, not be confused with the size and location-precision of the elements that can be represented in the maps. The latter is limited by certain factors that are intrinsic to the available input data:
 
 -   Ground Resolved Distance (GRD) is a metric that better reflects the spatial resolution of a satellite sensor than the spatial resolution of the image. For Sentinel-2 recent estimates suggest a GRD around 12.5 metres [10]
 -   To fully leverage Sentinel-2, the analyses of the time-series are essential. Since the completion of the reprocessing of Sentinel-2 Colllection-1 the multi-temporal co-registration is better than 4m in most cases whereas observations until August 2021 only had a co-registration accuracy of 12 metres before the reprocessing[^8].