Merge branch 'interface-single-weights' into 'main'

Adjusted single section interface weights to 50-50

See merge request ghsc/users/pmpowers/nshm-alaska!4

subduction/interface/Aleutian Arc/segmented/1-section/source-tree.json

 [
   {
     "id": "geodetic",
-    "weight": 0.2
+    "weight": 0.5
   },
   {
     "id": "geologic",
-    "weight": 0.8
+    "weight": 0.5
   }
 ]