web_component_studio script not working with Python 3.5
This script is not compatible with Python 3.5:
```
  File "scripts/web_component_studio/web_component_studio.py", line 54, in <module>
    with open(ROBOTS) as f:
TypeError: invalid file: PosixPath('/home/david/webots/scripts/web_component_studio/components.json')
```
(works fine with python 3.7).

We should either make it compatible with Python 3.5 or update the minimum required version.
diff --git a/scripts/web_component_studio/web_component_studio.py b/scripts/web_component_studio/web_component_studio.py
index 208cda5cd..a79c50082 100755
--- a/scripts/web_component_studio/web_component_studio.py
+++ b/scripts/web_component_studio/web_component_studio.py
@@ -31,9 +31,9 @@ assert WEBOTS_HOME, 'WEBOTS_HOME is undefined'
 
 # Paths.
 scriptdir = Path(getframeinfo(currentframe()).filename).resolve().parent
-WORLD = scriptdir / 'worlds' / 'web_component_studio.wbt'
-TEMPLATE = scriptdir / 'worlds' / 'web_component_studio_template.wbt'
-ROBOTS = scriptdir / 'components.json'
+WORLD = str(scriptdir / 'worlds' / 'web_component_studio.wbt')
+TEMPLATE = str(scriptdir / 'worlds' / 'web_component_studio_template.wbt')
+ROBOTS = str(scriptdir / 'components.json')
 
 
 def search_and_replace(filename, fromString, toString):
['scripts/web_component_studio/web_component_studio.py']