fix: Updating Webots road examples

[abanuelo]

Description

This PR introduces:

• New Grammar for EXTERNPROTO statements introduced in Webots >2022b.
• Added Grammar support for new lines between comments (ie #VRML_SIM R2023b utf8) and other grammar nodes
• Created a new berkeley.wbt file from the open street map data and used the Webots OpenStreetMap importer script to convert it to the 2023b .wbt file.
• Updated the .scenic examples within examples/webots/road to point to this new generated berkeley.wbt and updated the Scenic code to make sure examples work as expected

Issue Link

#262

Checklist

• I have tested the changes locally via pytest and/or other means
• I have added or updated relevant documentation
• I have autoformatted the code with black and isort
• I have added test cases (if applicable)

Additional Notes

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.17%. Comparing base (6f37d6c) to head (f5d06a4).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #268      +/-   ##
==========================================
- Coverage   91.17%   91.17%   -0.01%     
==========================================
  Files          54       54              
  Lines       13491    13493       +2     
==========================================
+ Hits        12301    12302       +1     
- Misses       1190     1191       +1     

see 6 files with indirect coverage changes