correct log messages for core validation (#389)

Co-authored-by: Pete Gadomski <[email protected]>

Author: ahill00

src/stac_api_validator/validations.py

@@ -746,13 +746,13 @@ def validate_core(
         errors += "/ : Link[rel=root] must exist"
     else:
         if not is_json_type(root.get("type")):
-            errors += f"/ : Link[rel=root] type is not application/geo+json, instead {root.get('type')}"
+            errors += f"/ : Link[rel=root] type is not application/json, instead {root.get('type')}"
 
     if not (_self := link_by_rel(links, "self")):
         warnings += "/ : Link[rel=self] must exist"
     else:
         if not is_json_type(_self.get("type")):
-            errors += f"/ : Link[rel=self] type is not application/geo+json, instead {_self.get('type')}"
+            errors += f"/ : Link[rel=self] type is not application/json, instead {_self.get('type')}"
 
     if not (service_desc := link_by_rel(links, "service-desc")):
         errors += "/ : Link[rel=service-desc] must exist"