Rename jp to ja

[ntotten]

What does this PR do?

Renames the localization folder jp to use the correct localization string ja

What issues does this PR fix or reference?

@W-7227338@

[codecov]

Codecov Report

Merging #1983 into develop will increase coverage by 10.79%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##           develop    #1983       +/-   ##
============================================
+ Coverage    73.17%   83.96%   +10.79%     
============================================
  Files          232       69      -163     
  Lines         8651     3099     -5552     
  Branches       987      294      -693     
============================================
- Hits          6330     2602     -3728     
+ Misses        2083      439     -1644     
+ Partials       238       58      -180

Impacted Files	Coverage Δ
...forcedx-apex-replay-debugger/src/messages/index.ts	41.66% <0%> (-8.34%)	⬇️
...scode-lwc/src/testSupport/testRunner/testRunner.ts
...rcedx-vscode-lwc/src/testSupport/commands/index.ts
...ges/salesforcedx-vscode-core/src/conflict/index.ts
.../src/commands/templates/forceLightningAppCreate.ts
...testSupport/commands/forceLwcTestNavigateToTest.ts
...rc/testSupport/commands/forceLwcTestWatchAction.ts
...lesforcedx-vscode-lwc/src/commands/commandUtils.ts
...rc/testSupport/testExplorer/testOutlineProvider.ts
...ore/src/commands/templates/internalCommandUtils.ts
... and 154 more

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[lcampos]

Looks good, I'll take care of merging this once I solve some merge conflicts