fix: Python/Automate_Image_Caption/requirements.txt to reduce vulnera…

…bilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-JUPYTERSERVER-7217832
- https://snyk.io/vuln/SNYK-PYTHON-TORNADO-7217828
- https://snyk.io/vuln/SNYK-PYTHON-TORNADO-7217829

Python/Automate_Image_Caption/requirements.txt

@@ -15,3 +15,5 @@ tensorboard-plugin-wit==1.7.0
 tensorflow==2.4.1
 tensorflow-estimator==2.4.0
 tqdm==4.56.0
+jupyter-server>=2.14.1 # not directly required, pinned by Snyk to avoid a vulnerability
+tornado>=6.4.1 # not directly required, pinned by Snyk to avoid a vulnerability