[djl-serving] update log4j configuration

[frankfliu]

Change-Id: I51f53056a152592cffbcf1e40ceca83c44e9c068

Description

Brief description of what this PR is about

• If this change is a backward incompatible change, why must this change be made?
• Interesting edge cases to note here

[codecov-commenter]

Codecov Report

Merging #1150 (cb9dee9) into master (0df8265) will decrease coverage by 0.00%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master    #1150      +/-   ##
============================================
- Coverage     70.26%   70.25%   -0.01%     
+ Complexity     5339     5338       -1     
============================================
  Files           513      513              
  Lines         23664    23664              
  Branches       2552     2552              
============================================
- Hits          16627    16625       -2     
- Misses         5674     5675       +1     
- Partials       1363     1364       +1     

Impacted Files	Coverage Δ
api/src/main/java/ai/djl/repository/Artifact.java	87.80% <0.00%> (-1.63%)	⬇️

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