fix(cli): add single-instance autostart init code

[Legend-Master]

Fix the generated plugin init code of tauri add for tauri-plugin-autostart and tauri-plugin-single-instance

Closes #13972

[github-actions]

Package Changes Through ebf0ed8

There are 8 changes which include tauri-cli with minor, @tauri-apps/cli with minor, tauri-utils with minor, tauri-bundler with patch, tauri-runtime-wry with patch, tauri with minor, @tauri-apps/api with minor, tauri-plugin with minor

Planned Package Versions

The following package releases are the planned based on the context of changes in this pull request.

package	current	next
@tauri-apps/api	2.7.0	2.8.0
tauri-utils	2.6.0	2.7.0
tauri-bundler	2.5.2	2.5.3
tauri-runtime	2.7.1	2.7.2
tauri-runtime-wry	2.7.2	2.7.3
tauri-codegen	2.3.1	2.3.2
tauri-macros	2.3.2	2.3.3
tauri-plugin	2.3.1	2.4.0
tauri-build	2.3.1	2.3.2
tauri	2.7.0	2.8.0
@tauri-apps/cli	2.7.1	2.8.0
tauri-cli	2.7.1	2.8.0

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