[6.0] Fix emailToPunycode() throws "Prohibited input U+0000005C"

[janschoenherr]

Pull Request for Issue #46356.

Summary of Changes

In Joomla 6 the algo26-matthias/idna-convert package got updated to version 4.2.1.

That library now throws an error when it encounters the ending com\.

With the change of this PR the thrown error is ignored and the email is kept.

This is the inital PR that introduced the emailToPunycode function:
#9041

Update

It seems to me, like the whole function was introduced because of the email cloaking plugin.
https://issues.joomla.org/tracker/joomla-cms/8881
That seems to be handling UTF-8 characters just fine now. Can we maybe remove that behavior from the ComponentHelper::filterText() function all together?

Testing Instructions

In Joomla 6 try to save an article with the following content

"mailto:[email protected]\"

Actual result BEFORE applying this Pull Request

Exception is thrown "Prohibited input U+0000005C"

Expected result AFTER applying this Pull Request

Article is saved.

Link to documentations

Please select:

• Documentation link for docs.joomla.org:

• No documentation changes for docs.joomla.org needed

• Pull Request link for manual.joomla.org:

• No documentation changes for manual.joomla.org needed

[tecpromotion]

I have tested this item ✅ successfully on 309a243

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[michaelmaass]

I have tested this item ✅ successfully on 309a243

Tested successfully! No error anymore.

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[tecpromotion]

RTC

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