MarsScenarioClientJoin test failing due to encoding mismatch

Description

I am encountering a test failure Microsoft.Data.SqlClient.ManualTesting.Tests.MARSTest.MarsScenarioClientJoin when running on Linux-x86 with CoreCLR:

```
[xUnit.net 00:00:01.31] Microsoft.Data.SqlClient.ManualTesting.Tests.MARSTest.MarsScenarioClientJoin [FAIL]
Error Message:
Assert.Equal() Failure: Strings differ
↓ (pos 23)
Expected: "Plutzer Lebensmittelgroßmärkte AG"
Actual: "Plutzer Lebensmittelgroßmärkte AG"
↑ (pos 23)
Stack Trace:
at Microsoft.Data.SqlClient.ManualTesting.Tests.MARSTest.MarsScenarioClientJoin() in /root/SqlClient/src/Microsoft.Data.SqlClient/tests/ManualTests/SQL/MARSTest/MARSTest.cs:line 639
```

It seems to be related to string encoding. Both the server and client locales are set to en_US.UTF-8, and I have tried other locales as well, but the test still fails.

Environment:
Test Machine OS: Linux
Runtime : Mono, CoreCLR
Affected Architectures: x86, s390x
Locale: en_US.UTF-8

cc @saitama951 @giritrivedi