Fix specifiers

Author: jochenklar

definitions/soc_dataset.yaml

@@ -848,7 +848,7 @@
     ISIMIP3b:
     - 1850-2015
 
-- specifier: reservoirs-dams
+- specifier: reservoirs-dams-group-3
   title: Reservoirs & dams (Group III)
   group: reservoirs-dams
   frequency: annual
@@ -992,7 +992,7 @@
     - 1850-2014
     - 2015-2100
 
-- specifier: water_abstraction
+- specifier: area_using_seawater_desalination
   title: Area Using Seawater Desalination
   group: desalination
   frequency: annual