Bump numpy from 1.16.4 to 1.21.0 in /examples

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

examples/requirements.txt

@@ -2,7 +2,7 @@ aim>=3.0.0
 Keras==2.2.4
 Keras-Applications==1.0.8
 Keras-Preprocessing==1.1.0
-numpy==1.16.4
+numpy==1.21.0
 Pillow>=7.1.0
 scikit-learn==0.21.2
 scipy==1.3.0