Bump matplotlib from 3.3.2 to 3.3.3 (#1930)

Bumps [matplotlib](https://github.com/matplotlib/matplotlib) from 3.3.2 to 3.3.3.
- [Release notes](https://github.com/matplotlib/matplotlib/releases)
- [Commits](https://github.com/matplotlib/matplotlib/compare/v3.3.2...v3.3.3)

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

requirements.txt

@@ -4,7 +4,7 @@ imbalanced-learn==0.7.0
 joblib==0.17.0
 libmozdata==0.1.68
 lmdb==0.99
-matplotlib==3.3.2
+matplotlib==3.3.3
 mercurial==5.5.2
 microannotate==0.0.21
 mozci==1.10.2