Bump nltk from 3.4.5 to 3.6.5

Bumps [nltk](https://github.com/nltk/nltk) from 3.4.5 to 3.6.5.
- [Release notes](https://github.com/nltk/nltk/releases)
- [Changelog](https://github.com/nltk/nltk/blob/develop/ChangeLog)
- [Commits](nltk/nltk@3.4.5...3.6.5)

---
updated-dependencies:
- dependency-name: nltk
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

requirements.txt

@@ -8,7 +8,7 @@ matplotlib>=3.1.2
 seaborn>=0.9.0
 fpdf==1.7.2
 wordcloud==1.5.0
-nltk==3.4.5
+nltk==3.6.5
 ordered-set>=3.1.0
 dill>=0.3.0
 yattag==1.12.2

setup.py

@@ -37,7 +37,7 @@ def get_version():
                       'seaborn>=0.9.0',
                       'fpdf==1.7.2',
                       'wordcloud==1.5.0',
-                      'nltk==3.4.5',
+                      'nltk==3.6.5',
                       'ordered-set>=3.1.0',
                       'lime>=0.1.1, <=2',
                       'dill>=0.3.0',