Fix "Warning: validateDOMNesting(...)" error

[luixxiul]

Fixes #11523

Follow-up to #11395

Auditors:

Test Plan:

1. Open about:preferences#payments

Submitter Checklist:

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Ran git rebase -i to squash commits (if needed).
• Tagged reviewers and labelled the pull request as needed.

Test Plan:

Reviewer Checklist:

Tests

• Adequate test coverage exists to prevent regressions
• Tests should be independent and work correctly when run individually or as a suite ref
• New files have MPL2 license header

[codecov-io]

Codecov Report

Merging #11524 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master   #11524   +/-   ##
=======================================
  Coverage   52.66%   52.66%           
=======================================
  Files         268      268           
  Lines       25218    25218           
  Branches     4022     4022           
=======================================
  Hits        13280    13280           
  Misses      11938    11938

Flag	Coverage Δ
#unittest	52.66% <100%> (ø)	⬆️

Impacted Files	Coverage Δ
...r/components/preferences/payment/enabledContent.js	91.24% <100%> (ø)	⬆️

[luixxiul]

master: 15303a9
0.21.x: 63de33f
0.20.x: 046b55c
0.19.x: 49731b5