ICU-22888 Configure XML processors / external DTDs

[mihnita]

Checklist

• Required: Issue filed: https://unicode-org.atlassian.net/browse/ICU-22888
• Required: The PR title must be prefixed with a JIRA Issue number. Example: "ICU-1234 Fix xyz"
• Required: The PR description must include the link to the Jira Issue, for example by completing the URL in the first checklist item
• Required: Each commit message must be prefixed with a JIRA Issue number. Example: "ICU-1234 Fix xyz"
• Issue accepted (done by Technical Committee after discussion)
• Tests included, if applicable
• API docs and/or User Guide docs changed or added, if applicable

[markusicu]

It looks like you meant to make these changes for ICU-22888 not for ICU-22917.

[jira-pull-request-webhook]

Hooray! The files in the branch are the same across the force-push. 😃

~ Your Friendly Jira-GitHub PR Checker Bot

[mihnita]

It looks like you meant to make these changes for ICU-22888 not for ICU-22917.

Sorry. Thanks. DONE.

[markusicu]

@mihnita remember to accept the ticket and merge this PR

[mihnita]

@mihnita remember to accept the ticket and merge this PR

I discovered that there is a PR for this already: #3243

So I reviewed it and waiting for them to update it, so that I can approve it.

I thing it would be good to let them do it.
It is their find, and their fix, not nice to "steal it".
And it might encourage them to contribute again :-)