Use latin character codes to fix test build on Windows

[labkey-tchad]

Rationale

Test build mangles UTF character literals on Windows.

[ant:iajc] private static final char WIDE_PLACEHOLDER = 'Î '; // Wide character can't be picked from the string with 'charAt'
[ant:iajc]                                              ^^^^
[ant:iajc] D:\teamcity\work\8063137bf091310a\server\testAutomation\src\org\labkey\test\util\TestDataGenerator.java:76:0::0 Invalid character constant

Related Pull Requests

• Update test helpers to understand field keys and names #2450

Changes

• Use latin character codes to fix test build on Windows