Fixed issue with md5 not support LargeUtf8 correctly

[Omega359]

Which issue does this PR close?

• Closes #13444
• Closes https://github.com/apache/datafusion/pull/13443

Rationale for this change

Bug fix for md5 not working as expected with largeutf8 input

What changes are included in this PR?

Code, tests.

Are these changes tested?

Yes

Are there any user-facing changes?

No

[alamb]

Since this is a small code / bug fix merging it in now