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GH-37378: [C++] Add A Dictionary Compaction Function For DictionaryArray (#37418)

### Rationale for this change
A Dictionary Compaction Function for DictionaryArray is supported.

### What changes are included in this PR?
Add a Function for Dictionary Compaction

### Are these changes tested?
Yes

Are there any user-facing changes?
No
* Closes: #37378

Lead-authored-by: Junming Chen <junming.chen.r@outlook.com>
Co-authored-by: Ben Harkins <60872452+benibus@users.noreply.github.com>
Co-authored-by: Benjamin Kietzman <bengilgit@gmail.com>
Signed-off-by: Benjamin Kietzman <bengilgit@gmail.com>