[SPARK-4116][YARN]Delete the abandoned log4j-spark-container.properties

[WangTaoTheTonic]

Since its name reduced at #560, the log4j-spark-container.properties was never used again.
And I have searched its name globally in code and found no cite.

[SparkQA]

Test build #22355 has started for PR 2977 at commit fb2729f.

• This patch merges cleanly.

[SparkQA]

Test build #22355 has finished for PR 2977 at commit fb2729f.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[AmplabJenkins]

Test PASSed.
Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/SparkPullRequestBuilder/22355/
Test PASSed.

[tgravescs]

this looks good.