Request code execution fails for a function without arguments
## Description
Impossible to submit an UserCode if the function doesn't have any argument, possible because the InputPolicy is initialized without any input_keys.

## How to Reproduce
```
import syft as sy

worker = sy.Worker(name="test")
node = worker.root_client
client = node.login(email="info@openmined.org", password="changethis")

@sy.syft_function(input_policy=sy.ExactMatch(),
                  output_policy=sy.SingleExecutionExactOutput())
def func():
    return 1

client.api.services.code.request_code_execution(func)
```

## Expected Behavior
This should not fail, currently, the error is:
![image](https://github.com/OpenMined/PySyft/assets/29687796/1d92c02f-7a93-4564-bbf8-689ebd6f45af)


## Additional Context
A workaround for this is submitting a dummy value to have the InputPolicy initialized.

```
import syft as sy

worker = sy.Worker(name="test")
node = worker.root_client
client = node.login(email="info@openmined.org", password="changethis")

import numpy as np
dummy_tensor = np.array([1,2,3])
dummy_action = sy.ActionObject.from_obj(dummy_tensor)
ptr = dummy_action.send(client)

@sy.syft_function(input_policy=sy.ExactMatch(dummy=ptr),
                  output_policy=sy.SingleExecutionExactOutput())
def func(dummy):
    return 1

client.api.services.code.request_code_execution(func)
```

diff --git a/packages/syft/src/syft/service/code/user_code.py b/packages/syft/src/syft/service/code/user_code.py
index 3b2b2acc9..9e57df475 100644
--- a/packages/syft/src/syft/service/code/user_code.py
+++ b/packages/syft/src/syft/service/code/user_code.py
@@ -571,7 +571,7 @@ def add_custom_status(context: TransformContext) -> TransformContext:
         node_view = NodeView(
             node_name=context.node.name, verify_key=context.node.signing_key.verify_key
         )
-        if node_view in input_keys:
+        if node_view in input_keys or len(input_keys) == 0:
             context.output["status"] = UserCodeStatusContext(
                 base_dict={node_view: UserCodeStatus.SUBMITTED}
             )
['packages/syft/src/syft/service/code/user_code.py']