add load localWitnessAccountAddress for keystore mode

[sean-liu55]

What does this PR do?
add load localWitnessAccountAddress for keystore mode

Why are these changes required?

This PR has been tested by:

• Unit Tests
• Manual Testing

Follow up

Extra details

[codecov-io]

Codecov Report

Merging #2457 into develop_v3.6.5 will decrease coverage by <.01%.
The diff coverage is 0%.

@@                 Coverage Diff                  @@
##             develop_v3.6.5    #2457      +/-   ##
====================================================
- Coverage             42.44%   42.43%   -0.01%     
  Complexity             4383     4383              
====================================================
  Files                   538      538              
  Lines                 32818    32825       +7     
  Branches               3633     3635       +2     
====================================================
  Hits                  13928    13928              
- Misses                17534    17541       +7     
  Partials               1356     1356

Impacted Files	Coverage Δ	Complexity Δ
src/main/java/org/tron/core/config/args/Args.java	61% <0%> (-0.55%)	146 <0> (ø)

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