Add F10 keybinding for debugger step, even on Web. (microsoft#183510)

Fixes microsoft#181792.
Previously, for Web the keyboard shortcut was Alt-F10, because it was
believed that F10 could not be bound on browsers. This turned out to be
incorrect, so we make the shortcut consistent (F10) with desktop VSCode
which is also what many other debuggers use.
We keep Alt-F10 on web as a secondary keybinding to keep the experience
some web users may have gotten used to by now.

Author: rehmsen

src/vs/workbench/contrib/debug/browser/debugCommands.ts

@@ -473,7 +473,8 @@ KeybindingsRegistry.registerCommandAndKeybindingRule({
 KeybindingsRegistry.registerCommandAndKeybindingRule({
 	id: STEP_OVER_ID,
 	weight: KeybindingWeight.WorkbenchContrib,
-	primary: isWeb ? (KeyMod.Alt | KeyCode.F10) : KeyCode.F10, // Browsers do not allow F10 to be binded so we have to bind an alternative
+	primary: KeyCode.F10,
+	secondary: isWeb ? [(KeyMod.Alt | KeyCode.F10)] : undefined, // Keep Alt-F10 for web for backwards-compatibility
 	when: CONTEXT_DEBUG_STATE.isEqualTo('stopped'),
 	handler: async (accessor: ServicesAccessor, _: string, context: CallStackContext | unknown) => {
 		const contextKeyService = accessor.get(IContextKeyService);