VSCode: ensure that text files are properly terminated per POSIX standard.

Text files should always end with a newline, so that all lines are complete
and simplistic tools do not skip the last line.
VSCode seems to apply this by default to py, but not to json files.

.vscode/settings.json

@@ -4,6 +4,7 @@
   "editor.formatOnType": true,
   "files.eol": "\n",
   "files.trimTrailingWhitespace": true,
+  "files.insertFinalNewline": true,  
   "python.linting.pylintEnabled": true,
   "python.linting.enabled": true,
   "python.formatting.provider": "black",
@@ -11,4 +12,4 @@
   "python.testing.pytestEnabled": true,
   "pylint.importStrategy": "fromEnvironment",
   "python.linting.lintOnSave": true,
-}
+}