Add basic trigonometric functions (#7258)

`math sin`
`math cos`
`math tan`

Support degrees with the flag `--degrees`/`-d`

crates/nu-command/src/default_context.rs

@@ -405,6 +405,9 @@ pub fn create_default_context() -> EngineState {
             MathStddev,
             MathSum,
             MathVariance,
+            MathSin,
+            MathCos,
+            MathTan,
             MathPi,
             MathEuler,
         };