DOC: remove duplicate whatsnew heading

Author: rcomer

doc/release/prev_whats_new/whats_new_3.10.0.rst

@@ -62,13 +62,6 @@ colour maps version 8.0.1 (DOI: https://doi.org/10.5281/zenodo.1243862).
     ax[2].imshow(img, cmap="vanimo")
 
 
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-Plotting and Annotation improvements
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 Plotting and Annotation improvements
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