chore(deps): bump xml range to 6.5.0

[khatruong2009]

Issue #, if available:
fixes #4297
Description of changes:

• Bumps xml range to 6.5.0
• The version is no longer pinned because version 6.3.0 contained a code change that required us to bump to 6.3.0 exclusively. We can return to the window since there are no code changes needed for 6.4.0-6.5.0.
• We also want to use the window because xml 6.5.0 requires SDK version 3.2.0, which would break us as we're using 3.0.1. Xml 6.4.0 also requires Dart 3.0 so going back to the window will allow customers to be more flexible with their dart version.

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