rel(1.2.0rc5): Update CHANGES [skip ci]
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First release in the 1.2.x series.
+ * FIX: Add DWI default patterns for dMRIPrep's reportlets (#504)
+ * FIX: Merge/SplitSeries write to path of input image, instead of cwd (#503)
* FIX: Better generalization and renaming+relocation in the API of ``extract_wm`` (#500)
* FIX: Increase fault tolerance of DerivativesDataSink (#497)
* FIX: Match N4-only workflow outputs to brain extraction workflow (#496)
