Stop nu panicks in math.round on a large decimal value(Most of the time) (#3224)

* Stop crashing when dealing with large numbers in math round

* Fix formatting

* add tests

* just to trigger wasm build

* trigger wasm build

crates/nu-command/tests/commands/math/mod.rs

@@ -1,6 +1,7 @@
 mod avg;
 mod eval;
 mod median;
+mod round;
 mod sum;
 
 use nu_test_support::{nu, pipeline};

crates/nu-command/tests/commands/math/round.rs

@@ -0,0 +1,21 @@
+use nu_test_support::nu;
+
+#[test]
+fn can_round_very_large_numbers() {
+    let actual = nu!(
+        cwd: ".",
+        "echo 18.1372544780074142289927665486772012345 | math round"
+    );
+
+    assert_eq!(actual.out, "18")
+}
+
+#[test]
+fn can_round_very_large_numbers_with_precision() {
+    let actual = nu!(
+        cwd: ".",
+        "echo 18.13725447800741422899276654867720121457878988 | math round -p 10"
+    );
+
+    assert_eq!(actual.out, "18.137254478")
+}