MLBEDSW-7546: Update lxml version to >= 4.5.2

- Python 3.9 requires lxml version >= 4.5.2

Signed-off-by: Alexander Hansson <Alexander.Hansson@arm.com>
Change-Id: I74f8f0bc0020e643779f2f52e4f6a7fdf6de4d67
diff --git a/pyproject.toml b/pyproject.toml
index 9332a3f..fbb7204 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -37,7 +37,7 @@
     "flatbuffers==2.0.7",
     "numpy<=1.21.3; python_version<='3.7'",
     "numpy; python_version>'3.7'",
-    "lxml>=4.5.1"
+    "lxml>=4.5.2"
 ]
 dynamic = ["readme", "version"]