optimize: When the number of primary keys exceeds 1000, use union to concatenate the SQL #6957

[remind]

…oncatenate the SQL (#6957)

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Ⅰ. Describe what this PR did

When the number of primary keys exceeds 1000, use union to concatenate the SQL

Ⅱ. Does this pull request fix one issue?

fixes #6957

Ⅲ. Why don't you add test cases (unit test/integration test)?

Ⅳ. Describe how to verify it

sql生成有测试用例：
io.seata.rm.datasource.SqlGenerateUtilsTest
此测试类之前已经存在，此次在此基础上进行了修改

其它受影响的地方依赖其它已有测试用例，由于该问题的触发场景比较极端，必须要超过1000个主键，并且该1000的配置是private的，有部分场景没看到之前有编写超过1000时的测试用例，本地通过修改配置值进行了单元测试，不确定集成测试是否有此场景的测试。

Ⅴ. Special notes for reviews

1、io.seata.rm.datasource.undo.AbstractUndoExecutor#queryCurrentRecords 该方法是使用了For Update，之前是一条sql一次性执行完，当主键数量超过1000时现在会拆分成多条sql循环执行，每条执行会有间隔，如果有同样的数据重复处理，并且是不同事务的，可能会导致死锁。

2、由于sql采用了union拼接，影响到了SQLSelectQueryBlock的获取，因此在*SelectForUpdateRecognizer此种类中，如io.seata.sqlparser.druid.mysql.MySQLSelectForUpdateRecognizer#getSelect，修改了获取方式，是否有可能造成影响。

[codecov]

Codecov Report

Attention: Patch coverage is 94.33962% with 3 lines in your changes missing coverage. Please review.

Project coverage is 52.63%. Comparing base (3b7e887) to head (95ea9ac).

Files with missing lines	Patch %	Lines
...qlparser/druid/dm/DmSelectForUpdateRecognizer.java	0.00%	1 Missing ⚠️
.../druid/oracle/OracleSelectForUpdateRecognizer.java	0.00%	1 Missing ⚠️
...ostgresql/PostgresqlSelectForUpdateRecognizer.java	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##                2.x    #7012      +/-   ##
============================================
+ Coverage     52.59%   52.63%   +0.03%     
- Complexity     6613     6622       +9     
============================================
  Files          1128     1128              
  Lines         40140    40149       +9     
  Branches       4704     4704              
============================================
+ Hits          21111    21131      +20     
+ Misses        17016    17003      -13     
- Partials       2013     2015       +2     

Files with missing lines	Coverage Δ
...g/apache/seata/rm/datasource/SqlGenerateUtils.java	96.22% <100.00%> (+1.10%)	⬆️
.../rm/datasource/exec/BaseTransactionalExecutor.java	74.12% <100.00%> (+0.12%)	⬆️
.../seata/rm/datasource/exec/MultiUpdateExecutor.java	80.00% <100.00%> (-0.27%)	⬇️
...pache/seata/rm/datasource/exec/UpdateExecutor.java	83.33% <100.00%> (-0.76%)	⬇️
...datasource/exec/mysql/MySQLUpdateJoinExecutor.java	77.56% <100.00%> (-0.70%)	⬇️
...seata/rm/datasource/undo/AbstractUndoExecutor.java	67.53% <100.00%> (+0.86%)	⬆️
...er/druid/mysql/MySQLSelectForUpdateRecognizer.java	78.37% <100.00%> (ø)
...id/sqlserver/SqlServerOperateRecognizerHolder.java	68.42% <100.00%> (ø)
...qlparser/druid/dm/DmSelectForUpdateRecognizer.java	0.00% <0.00%> (ø)
.../druid/oracle/OracleSelectForUpdateRecognizer.java	11.42% <0.00%> (ø)
... and 1 more

... and 2 files with indirect coverage changes