script: Bump robotframework python package version

Match https://github.com/renode/renode/commit/5a5922525

Change-Id: Ieee6f002a94327b8e3f439310a6b7748f376a3e2

python-requirements.txt

diff --git a/python-requirements.txt b/python-requirements.txt
index b37cf8c..d6fc26c 100644
--- a/python-requirements.txt
+++ b/python-requirements.txt
@@ -30,7 +30,7 @@
 pyfzf
 pyyaml
 requests
-robotframework==4.0.1
+robotframework==6.0.2
 scipy
 sel4-deps
 setuptools