Update backup command execution to use bash shell

- Modified the `execAsync` call in `postgres.ts` to specify the bash shell for executing backup commands, ensuring compatibility with bash-specific features.
- Removed the shebang line from the backup command script in `utils.ts` to streamline the script's execution context.

packages/server/src/utils/backups/postgres.ts

@@ -39,7 +39,9 @@ export const runPostgresBackup = async (
 		if (postgres.serverId) {
 			await execAsyncRemote(postgres.serverId, backupCommand);
 		} else {
-			await execAsync(backupCommand);
+			await execAsync(backupCommand, {
+				shell: "/bin/bash",
+			});
 		}
 
 		await sendDatabaseBackupNotifications({

packages/server/src/utils/backups/utils.ts

@@ -220,7 +220,6 @@ export const getBackupCommand = (
 	const containerSearch = getContainerSearchCommand(backup);
 	const backupCommand = generateBackupCommand(backup);
 	return `
-	#!/bin/bash
 	set -eo pipefail;
 	echo "[$(date)] Starting backup process..." >> ${logPath};
 	echo "[$(date)] Executing backup command..." >> ${logPath};