[MINOR] fix(mr): fix default value

[zhengchenyu]

What changes were proposed in this pull request?

When configured as README.md, MapReduce will throw these errors. It is not helpful for beginner.

Exception in thread "main" java.lang.IllegalArgumentException: mapreduce.rss.client.retry.max(100) * mapreduce.rss.client.retry.interval.max(10000) should not bigger than mapreduce.rss.client.send.check.timeout.ms(600000)
	at org.apache.hadoop.mapreduce.RssMRUtils.validateRssClientConf(RssMRUtils.java:307)
	at org.apache.hadoop.mapreduce.v2.app.RssMRAppMaster.main(RssMRAppMaster.java:189)

and

Exception in thread "main" java.lang.IllegalArgumentException: The value of null should be one of [GRPC_NETTY, GRPC]
	at org.apache.uniffle.client.util.ClientUtils.validateClientType(ClientUtils.java:144)
	at org.apache.hadoop.mapreduce.v2.app.RssMRAppMaster.main(RssMRAppMaster.java:141)

How was this patch tested?

test in yarn cluster.

[codecov-commenter]

Codecov Report

Merging #1035 (932c486) into master (ecfed5e) will increase coverage by 2.50%.
Report is 14 commits behind head on master.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master    #1035      +/-   ##
============================================
+ Coverage     54.10%   56.60%   +2.50%     
+ Complexity     2547     2078     -469     
============================================
  Files           382      317      -65     
  Lines         21728    13756    -7972     
  Branches       1802     1224     -578     
============================================
- Hits          11755     7786    -3969     
+ Misses         9269     5555    -3714     
+ Partials        704      415     -289     

see 100 files with indirect coverage changes

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[jerqi]

@zhengchenyu Could you run the command to fix style issues?

mvn spotless:apply -Pspark3 -Pspark2 -Ptez -Pmr -Phadoop2.8

[jerqi]

LGTM, merged to master. Thanks @zhengchenyu