election: provide methods to read and write campaignTimes instead of export

[JmPotato]

What problem does this PR solve?

Issue Number: ref #7499.

What is changed and how does it work?

Provide methods to read and write `campaignTimes` instead of export.

Check List

Tests

• Unit test
• Integration test

Release note

None.

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• CabinfeverB

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[codecov]

Codecov Report

Merging #7501 (f638b43) into master (4eac0ef) will increase coverage by 0.00%.
The diff coverage is n/a.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #7501   +/-   ##
=======================================
  Coverage   74.56%   74.56%           
=======================================
  Files         452      452           
  Lines       49934    49928    -6     
=======================================
- Hits        37234    37230    -4     
+ Misses       9377     9376    -1     
+ Partials     3323     3322    -1     

[JmPotato]

/merge

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This pull request has been accepted and is ready to merge.

Commit hash: f638b43