Support null in auto replies setting

Fixes microsoft#141666

Author: Tyriar

src/vs/workbench/contrib/terminal/common/terminalConfiguration.ts

@@ -508,8 +508,11 @@ const terminalConfiguration: IConfigurationNode = {
 			markdownDescription: localize('terminal.integrated.autoReplies', "A set of messages that when encountered in the terminal will be automatically responded to. Provided the message is specific enough, this can help automate away common responses. Note that the message includes escape sequences so the reply might not happen with styled text. Each reply can only happen once every second.\n\nTo unset a default key, set the value to null."),
 			type: 'object',
 			additionalProperties: {
-				type: 'string',
-				description: localize('terminal.integrated.autoReplies.reply', "The reply to send to the process.")
+				oneOf: [{
+					type: 'string',
+					description: localize('terminal.integrated.autoReplies.reply', "The reply to send to the process.")
+				},
+				{ type: 'null' }]
 			},
 			default: {
 				'Terminate batch job (Y/N)': 'Y\r'