views: Add Detected Environment section to About popup.

This includes the established Platform (PLATFORM), and the recent
addition of the python version and implementation.

Test updated.

Author: neiljp

tests/ui_tools/test_popups.py

@@ -259,6 +259,7 @@ def test_categories(self) -> None:
             "Application",
             "Server",
             "Application Configuration",
+            "Detected environment",
         ]
 
 

zulipterminal/ui_tools/views.py

@@ -41,6 +41,7 @@
     match_stream,
     match_user,
 )
+from zulipterminal.platform_code import PLATFORM, detected_python_in_full
 from zulipterminal.server_url import near_message_url
 from zulipterminal.ui_tools.boxes import PanelSearchBox
 from zulipterminal.ui_tools.buttons import (
@@ -1104,6 +1105,10 @@ def __init__(
                     ("Notifications", "enabled" if notify_enabled else "disabled"),
                 ],
             ),
+            (
+                "Detected environment",
+                [("Platform", PLATFORM), ("Python", detected_python_in_full())],
+            ),
         ]
 
         popup_width, column_widths = self.calculate_table_widths(contents, len(title))