GH-35937: [R] Update NEWS for 12.0.1 (#35938)

Lead-authored-by: Nic Crane <[email protected]>
Co-authored-by: Dewey Dunnington <[email protected]>
Signed-off-by: Nic Crane <[email protected]>

Author: 2 people

r/NEWS.md

@@ -17,6 +17,12 @@
   under the License.
 -->
 
+# arrow 12.0.0.9000
+
+* Update the version of the date library vendored with Arrow C++ library 
+  for compatibility with tzdb 0.4.0 (#35594, #35612).
+* Update some tests for compatibility with waldo 0.5.1 (#35131, #35308).
+
 # arrow 12.0.0
 
 ## New features