docs: Fix shell setting doc (#17208)

Release Notes:

- N/A


https://github.com/zed-industries/zed/blob/03fd5c90d8901f91e03578ac46a169ef8d997f70/crates/project/src/project.rs#L5210


https://github.com/zed-industries/zed/blob/03fd5c90d8901f91e03578ac46a169ef8d997f70/crates/task/src/lib.rs#L266

assets/settings/default.json

@@ -603,7 +603,7 @@
     //     "shell": {
     //         "with_arguments": {
     //           "program": "/bin/bash",
-    //           "arguments": ["--login"]
+    //           "args": ["--login"]
     //         }
     //     }
     "shell": "system",

assets/settings/initial_tasks.json

@@ -35,7 +35,7 @@
     //     "shell": {
     //         "with_arguments": {
     //           "program": "/bin/bash",
-    //           "arguments": ["--login"]
+    //           "args": ["--login"]
     //         }
     //     }
     "shell": "system"

docs/src/tasks.md

@@ -37,7 +37,7 @@ Zed supports ways to spawn (and rerun) commands using its integrated terminal to
     //     "shell": {
     //         "with_arguments": {
     //           "program": "/bin/bash",
-    //           "arguments": ["--login"]
+    //           "args": ["--login"]
     //         }
     //     }
     "shell": "system"