remove duplicated conf.set() in TestScriptBasedMapping

[shuaiwang516]

Description of PR

There is a duplicated conf.set() in TestScriptBasedMapping#testNoArgsMeansNoResult.
This PR removes the duplicated line.

How was this patch tested?

Rerun TestScriptBasedMapping#testNoArgsMeansNoResult and pass without any failure/error.

[hadoop-yetus]

🎊 +1 overall

Vote	Subsystem	Runtime	Logfile	Comment
+0 🆗	reexec	1m 1s		Docker mode activated.
			_ Prechecks _
+1 💚	dupname	0m 0s		No case conflicting files found.
+0 🆗	codespell	0m 0s		codespell was not available.
+0 🆗	detsecrets	0m 0s		detect-secrets was not available.
+1 💚	@author	0m 0s		The patch does not contain any @author tags.
+1 💚	test4tests	0m 0s		The patch appears to include 1 new or modified test files.
			_ trunk Compile Tests _
+1 💚	mvninstall	40m 49s		trunk passed
+1 💚	compile	25m 11s		trunk passed with JDK Private Build-11.0.15+10-Ubuntu-0ubuntu0.20.04.1
+1 💚	compile	21m 54s		trunk passed with JDK Private Build-1.8.0_312-8u312-b07-0ubuntu1~20.04-b07
+1 💚	checkstyle	1m 30s		trunk passed
+1 💚	mvnsite	1m 59s		trunk passed
+1 💚	javadoc	1m 35s		trunk passed with JDK Private Build-11.0.15+10-Ubuntu-0ubuntu0.20.04.1
+1 💚	javadoc	1m 5s		trunk passed with JDK Private Build-1.8.0_312-8u312-b07-0ubuntu1~20.04-b07
+1 💚	spotbugs	3m 3s		trunk passed
+1 💚	shadedclient	25m 49s		branch has no errors when building and testing our client artifacts.
			_ Patch Compile Tests _
+1 💚	mvninstall	1m 6s		the patch passed
+1 💚	compile	24m 19s		the patch passed with JDK Private Build-11.0.15+10-Ubuntu-0ubuntu0.20.04.1
+1 💚	javac	24m 19s		the patch passed
+1 💚	compile	21m 55s		the patch passed with JDK Private Build-1.8.0_312-8u312-b07-0ubuntu1~20.04-b07
+1 💚	javac	21m 55s		the patch passed
+1 💚	blanks	0m 0s		The patch has no blanks issues.
+1 💚	checkstyle	1m 24s		the patch passed
+1 💚	mvnsite	2m 0s		the patch passed
+1 💚	javadoc	1m 24s		the patch passed with JDK Private Build-11.0.15+10-Ubuntu-0ubuntu0.20.04.1
+1 💚	javadoc	1m 6s		the patch passed with JDK Private Build-1.8.0_312-8u312-b07-0ubuntu1~20.04-b07
+1 💚	spotbugs	3m 2s		the patch passed
+1 💚	shadedclient	26m 22s		patch has no errors when building and testing our client artifacts.
			_ Other Tests _
+1 💚	unit	18m 16s		hadoop-common in the patch passed.
+1 💚	asflicense	1m 18s		The patch does not generate ASF License warnings.
		227m 0s

Subsystem	Report/Notes
Docker	ClientAPI=1.41 ServerAPI=1.41 base: https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-4509/1/artifact/out/Dockerfile
GITHUB PR	#4509
Optional Tests	dupname asflicense compile javac javadoc mvninstall mvnsite unit shadedclient spotbugs checkstyle codespell detsecrets
uname	Linux c3d01a9e1a1b 4.15.0-175-generic #184-Ubuntu SMP Thu Mar 24 17:48:36 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	dev-support/bin/hadoop.sh
git revision	trunk / 48f1a15
Default Java	Private Build-1.8.0_312-8u312-b07-0ubuntu1~20.04-b07
Multi-JDK versions	/usr/lib/jvm/java-11-openjdk-amd64:Private Build-11.0.15+10-Ubuntu-0ubuntu0.20.04.1 /usr/lib/jvm/java-8-openjdk-amd64:Private Build-1.8.0_312-8u312-b07-0ubuntu1~20.04-b07
Test Results	https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-4509/1/testReport/
Max. process+thread count	1253 (vs. ulimit of 5500)
modules	C: hadoop-common-project/hadoop-common U: hadoop-common-project/hadoop-common
Console output	https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-4509/1/console
versions	git=2.25.1 maven=3.6.3 spotbugs=4.2.2
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[ayushtkn]

you need to create a Jira as well in Hadoop to get this committed.
Read:
https://cwiki.apache.org/confluence/display/hadoop/how+to+contribute

If you still have any trouble doing so, let me know, will try to help..

[github-actions]

We're closing this stale PR because it has been open for 100 days with no activity. This isn't a judgement on the merit of the PR in any way. It's just a way of keeping the PR queue manageable.
If you feel like this was a mistake, or you would like to continue working on it, please feel free to re-open it and ask for a committer to remove the stale tag and review again.
Thanks all for your contribution.