public static Set<String> getReservedNames() {
        Set<String> temp = new HashSet<>();
        Arrays.stream(RankingExpressionParserConstants.tokenImage)
                .map(token -> token.substring(1, token.length()-1)).forEach(name -> temp.add(name));
        temp.add("attribute");
        temp.add("constant");
        temp.add("customTokenInputIds");
        temp.add("firstphase");
        temp.add("globalphase");
        temp.add("normalize_linear");
        temp.add("onnx");
        temp.add("onnx_vespa");
        temp.add("query");
        temp.add("reciprocal_rank");
        temp.add("reciprocal_rank_fusion");
        temp.add("secondphase");
        temp.add("tensor");
        temp.add("tokenAttentionMask");
        temp.add("tokenInputIds");
        temp.add("tokenTypeIds");
        temp.add("value");
        temp.add("xgboost");
        return Set.copyOf(temp);
    }
Issues a warning if some function has a reserved name. This is not necessarily
an error, as a rank profile function can shadow a built-in function.

@author lesters
config-model/src/main/java/com/yahoo/schema/processing/ReservedFunctionNames.java