Method to Test Whether Csv Will Be Affected by Php9

[oleibman]

See #4161. The best way to future-proof is to set the escape character to null string, and set testAutoDetect to false before reading. However, depending on the file being read, this may lead to different results than expected. This will be unavoidable because Php itself will change. This PR adds a new static method affectedByPhp9 to Csv Reader. This can be used to identify in advance whether an input file will be affected by the changes. This will allow users to identify problems in advance, and prepare for how they might be handled.

This is:

• a bugfix
• a new feature
• refactoring
• additional unit tests

Checklist:

• Changes are covered by unit tests
  • Changes are covered by existing unit tests
  • New unit tests have been added
• Code style is respected
• Commit message explains why the change is made (see https://github.com/erlang/otp/wiki/Writing-good-commit-messages)
• CHANGELOG.md contains a short summary of the change and a link to the pull request if applicable
• Documentation is updated as necessary

Why this change is needed?

Provide an explanation of why this change is needed, with links to any Issues (if appropriate).
If this is a bugfix or a new feature, and there are no existing Issues, then please also create an issue that will make it easier to track progress with this PR.