Repository: Qiskit/qiskit

Issue:
Data parameter from Operator class does not show properly in API reference 
### Environment

- **Qiskit Terra version**: N/A
- **Python version**: N/A
- **Operating system**: N/A


### What is happening?

The part of the `Operator` class [API reference page](https://qiskit.org/documentation/stubs/qiskit.quantum_info.Operator.html) from `qiskit.quantum_info` in which the parameters are listed does not show properly. In particular, where the data argument is supposed to be the page reads:

> Parameters
or (data ([QuantumCircuit](https://qiskit.org/documentation/stubs/qiskit.circuit.QuantumCircuit.html#qiskit.circuit.QuantumCircuit)) – Instruction or BaseOperator or matrix): data to initialize operator.

Instead of 

> Parameters
data ([QuantumCircuit](https://qiskit.org/documentation/stubs/qiskit.circuit.QuantumCircuit.html#qiskit.circuit.QuantumCircuit) or Instruction or BaseOperator or matrix): data to initialize operator.

However I don't see any problem with the source code:
```
def __init__(self, data, input_dims=None, output_dims=None):
        """Initialize an operator object.

        Args:
            data (QuantumCircuit or
                  Instruction or
                  BaseOperator or
                  matrix): data to initialize operator.
            input_dims (tuple): the input subsystem dimensions.
                                [Default: None]
            output_dims (tuple): the output subsystem dimensions.
                                 [Default: None]

```

### How can we reproduce the issue?

* Open the `Operator` class [API reference page](https://qiskit.org/documentation/stubs/qiskit.quantum_info.Operator.html).
* Check the parameters section

### What should happen?

You should see the aforementioned error.

### Any suggestions?

_No response_


Discussion:
Thank you for finding the bug!

As a follow up, could there be an issue with how the docstring is formatted? I am not very familiar with how the docstring is parsed using Napoleon (a Sphinx extension), but maybe the colon should be on the same line as `data`!? Maybe something like this:
```
Args:
      data (QuantumCircuit or Operation or BaseOperator or matrix): 
                          data to initialize operator.
      input_dims (tuple): the input subsystem dimensions.
                          [Default: None]
      output_dims (tuple): the output subsystem dimensions.
                           [Default: None]
```

Note also that due to some recent update in the operator.py file, the correct line that should appear in the API reference page is

>data (QuantumCircuit or Operation or BaseOperator or matrix): data to initialize operator.

That is, `Instruction` has been replaced by `Operation`.
@dalin27: yeah, I would expect that Sphinx's parser is probably choking because it's not finding the colon.  Putting it on one line should help out.

The online documentation still says `Instruction` because the online documentation is for Terra 0.21.2, and the `Operation` interface is only on the main branch, and planned to be released in Terra 0.22.  We're not planning to release a 0.21.3 patch (unless something _super_ critical happens very soon), so any documentation fix would go out with 0.22.

Resolving patch:
diff --git a/qiskit/quantum_info/operators/operator.py b/qiskit/quantum_info/operators/operator.py
--- a/qiskit/quantum_info/operators/operator.py
+++ b/qiskit/quantum_info/operators/operator.py
@@ -53,10 +53,8 @@ def __init__(self, data, input_dims=None, output_dims=None):
         """Initialize an operator object.
 
         Args:
-            data (QuantumCircuit or
-                  Operation or
-                  BaseOperator or
-                  matrix): data to initialize operator.
+            data (QuantumCircuit or Operation or BaseOperator or matrix):
+                                data to initialize operator.
             input_dims (tuple): the input subsystem dimensions.
                                 [Default: None]
             output_dims (tuple): the output subsystem dimensions.


Test patch: