Missing check when creating weight load balancing algorithm

[RaigorJiang]

Bug Report

Which version of ShardingSphere did you use?

5.5.1-SNAPSHOT d52db30

Which project did you use? ShardingSphere-JDBC or ShardingSphere-Proxy?

ShardingSphere-Proxy

Expected behavior

If a non-existent storage unit is referenced when creating a rule, an exception should be prompted

Actual behavior

The rule persistence succeeded, but the metadata refresh failed

Steps to reproduce the behavior, such as: SQL to execute, sharding rule configuration, when exception occur etc.

1. DistSQL

create database readwrite_splitting_db;

use readwrite_splitting_db;

REGISTER STORAGE UNIT write_ds_0 (
    URL="jdbc:mysql://127.0.0.1:3306/write_ds_0?serverTimezone=UTC&useSSL=false&allowPublicKeyRetrieval=true",
    USER="root",
    PASSWORD="123456",
    PROPERTIES("maximumPoolSize"=10)
), read_ds_0_0 (
    URL="jdbc:mysql://127.0.0.1:3306/read_ds_0_0?serverTimezone=UTC&useSSL=false&allowPublicKeyRetrieval=true",
    USER="root",
    PASSWORD="123456",
    PROPERTIES("maximumPoolSize"=10)
), read_ds_0_1 (
    URL="jdbc:mysql://127.0.0.1:3306/read_ds_0_1?serverTimezone=UTC&useSSL=false&allowPublicKeyRetrieval=true",
    USER="root",
    PASSWORD="123456",
    PROPERTIES("maximumPoolSize"=10)
);

-- Note that read_ds_0_2 does not exist
CREATE READWRITE_SPLITTING RULE group_0 (
    WRITE_STORAGE_UNIT=write_ds_0,
    READ_STORAGE_UNITS(read_ds_0_0,read_ds_0_1),
    TRANSACTIONAL_READ_QUERY_STRATEGY='PRIMARY',
    TYPE(NAME="WEIGHT", PROPERTIES("read_ds_0_0"="5", "read_ds_0_2"="5"))
);

2. Proxy log