Merge pull request #6 from opennlp/dependabot/pip/tensorflow-2.5.1

Bump tensorflow from 1.15.2 to 2.5.1

Author: rupakc

requirements.txt

@@ -6,7 +6,7 @@ numpy==1.15.4
 pymongo==3.6.1
 six==1.11.0
 pymagnitude==0.1.120
-tensorflow==1.15.2
+tensorflow==2.5.1
 tensorflow_hub==0.2.0
 sentencepiece==0.1.8
 lime==0.1.1.32