docs: extend description of dataScience.runStartupCommands (#7216)

Author: janosh

package.json

@@ -1936,7 +1936,6 @@
                     "description": "Path to mypy, you can use a custom version of mypy by modifying this setting to include the full path.",
                     "scope": "resource"
                 },
-
                 "python.linting.pycodestyleArgs": {
                     "type": "array",
                     "description": "Arguments passed in. Each argument is a separate item in the array.",
@@ -2341,7 +2340,7 @@
                 "python.dataScience.runStartupCommands": {
                     "type": "string",
                     "default": "",
-                    "description": "A series of Python instructions that will be executed when the interactive window loads.",
+                    "description": "A series of Python instructions or iPython magic commands separated by '\n' that will be executed when the interactive window loads. For instance, set this to '%load_ext autoreload\n%autoreload 2' to automatically reload changes made to imported files without having to restart the interactive session.",
                     "scope": "resource"
                 },
                 "python.dataScience.debugJustMyCode": {