fix: Enterprise Github instance endpoint

apps/ui/src/routes/sources/[id]/_Github.svelte

@@ -36,10 +36,14 @@
 
 	async function installRepositories(source: any) {
 		const { htmlUrl } = source;
+        let endpoint = 'apps'
+        if (htmlUrl !== 'https://github.com') {
+            endpoint = 'github-apps'
+        }
 		const left = screen.width / 2 - 1020 / 2;
 		const top = screen.height / 2 - 1000 / 2;
 		const newWindow = open(
-			`${htmlUrl}/apps/${source.githubApp.name}/installations/new`,
+			`${htmlUrl}/${endpoint}/${source.githubApp.name}/installations/new`,
 			'GitHub',
 			'resizable=1, scrollbars=1, fullscreen=0, height=1000, width=1020,top=' +
 				top +