Fix custom test for PluralRules options parameter (#1612)

Author: queengooborg

custom/tests.yaml

@@ -6610,8 +6610,8 @@ javascript:
             }
           __additional:
             options_parameter: |-
-              // The roundingIncrement parameter was one of the first options available
-              return bcd.testOptionParam(construct, null, 'roundingIncrement', 200);
+              // The roundingPriority parameter was one of the first options available
+              return bcd.testOptionParam(construct, null, 'roundingPriority', 'lessPrecision');
             options_parameter.options_roundingIncrement_parameter: return bcd.testOptionParam(construct, null, 'roundingIncrement', 200);
             options_parameter.options_roundingMode_parameter: return bcd.testOptionParam(construct, null, 'roundingMode', 'floor');
             options_parameter.options_roundingPriority_parameter: return bcd.testOptionParam(construct, null, 'roundingPriority', 'lessPrecision');