Pin the precise version of MarkupSafe in python deps

Jinja2 deps list contains a too wide range of acceptable MarkupSafe versions,
as a result MarkupSafe v2.1.0 contains changes that break Jinja2
See pallets/markupsafe#286

builder/frameworks/freedom-e-sdk.py

@@ -34,7 +34,9 @@
 except ImportError:
     env.Execute(
         env.VerboseAction(
-            "$PYTHONEXE -m pip install pyparsing==2.4.5 Jinja2==2.10.1",
+            # Note: a specific version of MarkupSafe is requrired to avoid
+            # the ImportError of 'soft_unicode' in Jinja2
+            "$PYTHONEXE -m pip install pyparsing==2.4.5 MarkupSafe==2.0.1 Jinja2==2.10.1",
             "Installing Freedom E SDK's Python dependencies",
         )
     )