Update scala-xml to 2.1.0

[scala-steward]

Updates org.scala-lang.modules:scala-xml from 2.0.1 to 2.1.0.
GitHub Release Notes - Version Diff

I'll automatically update this PR to resolve conflicts as long as you don't change it yourself.

If you'd like to skip this version, you can just close this PR. If you have any feedback, just mention me in the comments below.

Configure Scala Steward for your repository with a .scala-steward.conf file.

Have a fantastic day writing Scala!

Files still referring to the old version number

The following files still refer to the old version number (2.0.1).
You might want to review and update them manually.

containers/release-candidate/setup-container.sh

Ignore future updates

Add this to your .scala-steward.conf file to ignore future updates of this dependency:

updates.ignore = [ { groupId = "org.scala-lang.modules", artifactId = "scala-xml" } ]

labels: library-update, early-semver-minor, semver-spec-minor, old-version-remains, commit-count:1

[tuxji]

Scala XML v2.1.0 no longer ignores XML comments, XML CDATA sections, or nodes before and after the root element. Those changes have broken several Daffodil tests that used to work with Scala XML v2.0.1; we will need someone very knowledgeable about how Daffodil uses Scala XML like @mbeckerle to check these tests and decide whether we can just change the failing tests or might need to make more extensive fixes to Daffodil code.

GitHub Release Notes - Version Diff

[mbeckerle]

Let's leave this PR open. I'll create a JIRA ticket for upgrade to Scala XML 2.1.0 version.

We really do have to look at this carefully. Scala XML support is evolving radically in the transition from Scala 2.12 to 2.13 and 3.x. (I have my doubts about whether we will ever upgrade to Scala 3 actually)

OTOH: there are some annoying XML bugs that really do actually impact DFDL schemas - e.g., scala xml not handling character 0xB properly, etc. that actually are hard to work around for us. I'm hoping these are fixed in scala xml 2.1.0.

But that said, no point putting a great deal of work into fixing this if it's all going to be scrap when we upgrade to a newer Scala.

[mbeckerle]

See https://issues.apache.org/jira/browse/DAFFODIL-2685

[stevedlawrence]

Should we close this PR now that we have the JIRA issue to track the upgrade? This PR will never be merged until someone takes on the issue and fixes the regressions, at which point they can create a new PR, so this is sort of just a distraction.

[mbeckerle]

Yes I suppose we should just close it. Closing.