Use more relevant page for "Help > Environment" menu item target

Selecting "Help > Environment" from the Arduino IDE menus opens a page containing usage information for the Arduino IDE
application in the browser.

Previously, the URL used was the same as that of in Arduino IDE 1.x:

https://www.arduino.cc/en/Guide/Environment

The documentation from that page was written for Arduino IDE 1.x. Even though the UI of the two versions is aligned for
the most part, some advancements made for the 2.x major version series resulted in some differences. This means that
documentation targeted at Arduino IDE 1.x is not always applicable to Arduino IDE 2.x.

Fortunately, documentation is now available for each major version series of the IDE. So resolution is only a matter of
pointing the menu item at the correct URL.

Author: per1234

Diff for: arduino-ide-extension/src/browser/contributions/help.ts

@@ -41,7 +41,9 @@ export class Help extends Contribution {
     );
     registry.registerCommand(
       Help.Commands.ENVIRONMENT,
-      createOpenHandler('https://www.arduino.cc/en/Guide/Environment')
+      createOpenHandler(
+        'https://docs.arduino.cc/software/ide-v2/tutorials/getting-started-ide-v2'
+      )
     );
     registry.registerCommand(
       Help.Commands.TROUBLESHOOTING,