fix(postgrest): Update parameter type of isFilter() to only allow b…

…oolean or null (#920)

fix: parameter type of isFilter

packages/postgrest/lib/src/postgrest_filter_builder.dart

@@ -230,7 +230,7 @@ class PostgrestFilterBuilder<T> extends PostgrestTransformBuilder<T> {
   ///     .isFilter('data', null);
   /// ```
   // ignore: non_constant_identifier_names
-  PostgrestFilterBuilder<T> isFilter(String column, Object? value) {
+  PostgrestFilterBuilder<T> isFilter(String column, bool? value) {
     return copyWithUrl(appendSearchParams(column, 'is.$value'));
   }