R4R: Return an empty TxResponse

[alexanderbez]

closes: #3585

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• Targeted PR against correct branch (see CONTRIBUTING.md)

• Linked to github-issue with discussion and accepted design OR link to spec that describes this work.

• Wrote tests

• Updated relevant documentation (docs/)

• Added entries in PENDING.md with issue #

• rereviewed Files changed in the github PR explorer

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For Admin Use:

• Added appropriate labels to PR (ex. wip, ready-for-review, docs)
• Reviewers Assigned
• Squashed all commits, uses message "Merge pull request #XYZ: [title]" (coding standards)

[codecov]

Codecov Report

Merging #3624 into develop will decrease coverage by 0.04%.
The diff coverage is 0%.

@@             Coverage Diff             @@
##           develop    #3624      +/-   ##
===========================================
- Coverage     61.3%   61.26%   -0.05%     
===========================================
  Files          186      186              
  Lines        13992    13998       +6     
===========================================
- Hits          8578     8576       -2     
- Misses        4870     4878       +8     
  Partials       544      544

[cwgoes]

ACK

[jackzampolin]

LGTM 👍