optimize : appdata size limit

[Bughue]

Ⅰ. Describe what this PR did

新增判断：一阶段上传的appdata数据大小。TC和RM都有判断。除了抛出错误的判断值也加入了warningsize的值，作为用户数据越来越大时的一个提醒。

Ⅱ. Does this pull request fix one issue?

fixes https://github.com/seata/seata/issues/4421

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

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

[Bughue]

提醒自己：应该要把配置key写到文档

[codecov-commenter]

Codecov Report

Merging #4473 (df1c0ad) into 2.x (2122c6d) will increase coverage by 0.02%. The diff coverage is 42.55%.

Additional details and impacted files

@@             Coverage Diff              @@
##                2.x    #4473      +/-   ##
============================================
+ Coverage     49.54%   49.57%   +0.02%     
- Complexity     4766     4786      +20     
============================================
  Files           909      909              
  Lines         31390    31418      +28     
  Branches       3782     3778       -4     
============================================
+ Hits          15553    15575      +22     
- Misses        14300    14312      +12     
+ Partials       1537     1531       -6     

Files	Coverage Δ
...c/main/java/io/seata/common/ConfigurationKeys.java	0.00% <ø> (ø)
...n/src/main/java/io/seata/common/DefaultValues.java	0.00% <ø> (ø)
...java/io/seata/server/coordinator/AbstractCore.java	54.73% <66.66%> (+0.71%)	:arrow_up:
.../autoconfigure/properties/client/RmProperties.java	37.70% <25.00%> (-1.92%)	:arrow_down:
...oconfigure/properties/server/ServerProperties.java	27.27% <25.00%> (-0.51%)	:arrow_down:
...rc/main/java/io/seata/common/util/StringUtils.java	44.48% <45.45%> (+3.41%)	:arrow_up:

... and 8 files with indirect coverage changes

[CLAassistant]

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[Bughue]

script folder in the config.txt, application.properties/yml, file.conf, and server example thatyml to add configuration, springboot-autoconfigure module to add the corresponding configuration examples

script文件夹中的config.txt,application.properties/yml，file.conf，和server的example那个yml要补充配置，springboot-autoconfigure模块要补充对应的配置示例

DONE

[Bughue]

文档更新 https://github.com/seata/seata.github.io/pull/681