chore: add test for tx priority (backport #2394)

[mergify]

This is an automatic backport of pull request #2394 done by Mergify.
Cherry-pick of 58c1e4e has failed:

On branch mergify/bp/v1.x/pr-2394
Your branch is up to date with 'origin/v1.x'.

You are currently cherry-picking commit 58c1e4e.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	new file:   app/test/priority_test.go
	modified:   pkg/user/tx_options.go

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   Makefile

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/github/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

---

Mergify commands and options

More conditions and actions can be found in the documentation.

You can also trigger Mergify actions by commenting on this pull request:

• @Mergifyio refresh will re-evaluate the rules
• @Mergifyio rebase will rebase this PR on its base branch
• @Mergifyio update will merge the base branch into this PR
• @Mergifyio backport <destination> will backport this PR on <destination> branch

Additionally, on Mergify dashboard you can:

• look at your merge queues
• generate the Mergify configuration with the config editor.

Finally, you can contact us on https://mergify.com

[evan-forbes]

apparently we never ported the make test-race changes back, same with two other test helpers that are in the priority test

[codecov-commenter]

Codecov Report

Merging #2400 (20ab76e) into v1.x (0d26707) will decrease coverage by 0.02%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             v1.x    #2400      +/-   ##
==========================================
- Coverage   20.49%   20.47%   -0.02%     
==========================================
  Files         138      138              
  Lines       15788    15798      +10     
==========================================
  Hits         3235     3235              
- Misses      12246    12256      +10     
  Partials      307      307              

Files Changed	Coverage Δ
pkg/user/tx_options.go	0.00% <0.00%> (ø)