test: Change instances of messages to enContent while importing from locales

[SamuelSalas]

Description

We want to improve the variable name we use while importing from the locales folder. "Messages" is a bit unclear and can cause confusion. The purpose here is to rename to "enContent".

Related issues

Fixes: 1510

Manual testing steps

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Screenshots/Recordings

Before

After

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• I've completed the PR template to the best of my ability
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[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarCloud

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 45.95%. Comparing base (d1d5c00) to head (eae0fba).
Report is 24 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9197      +/-   ##
==========================================
- Coverage   45.98%   45.95%   -0.04%     
==========================================
  Files        1273     1277       +4     
  Lines       31342    31538     +196     
  Branches     3213     3248      +35     
==========================================
+ Hits        14414    14493      +79     
- Misses      16079    16190     +111     
- Partials      849      855       +6     

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[Andepande]

LG