Make the math commands const (#13566)

This PR closes [Issue
#13482](https://github.com/nushell/nushell/issues/13482)

# Description
This PR tend to make all math function to be constant. 

# User-Facing Changes
The math commands now can be used as constant methods.

### Some Example
```
> const MODE = [3 3 9 12 12 15] | math mode
> $MODE
╭───┬────╮
│ 0 │  3 │
│ 1 │ 12 │
╰───┴────╯

> const LOG = [16 8 4] | math log 2
> $LOG
╭───┬──────╮
│ 0 │ 4.00 │
│ 1 │ 3.00 │
│ 2 │ 2.00 │
╰───┴──────╯

> const VAR = [1 3 5] | math variance
> $VAR
2.6666666666666665
```

# Tests + Formatting
Tests are added for all of the math command to test there constant
behavior.

I mostly focused on the actual user experience, not the correctness of
the methods and algorithms.

# After Submitting
I think this change don't require any additional documentation. Feel
free to correct me in this topic please.

crates/nu-command/src/math/product.rs

@@ -32,6 +32,10 @@ impl Command for SubCommand {
         vec!["times", "multiply", "x", "*"]
     }
 
+    fn is_const(&self) -> bool {
+        true
+    }
+
     fn run(
         &self,
         _engine_state: &EngineState,
@@ -42,6 +46,15 @@ impl Command for SubCommand {
         run_with_function(call, input, product)
     }
 
+    fn run_const(
+        &self,
+        _working_set: &StateWorkingSet,
+        call: &Call,
+        input: PipelineData,
+    ) -> Result<PipelineData, ShellError> {
+        run_with_function(call, input, product)
+    }
+
     fn examples(&self) -> Vec<Example> {
         vec![
             Example {