Show error when trying to sort by invalid column (#1880)

* Show error when trying to sort by invalid column

* Added test for changes

* Addressed comments, updated test

* Removed unnecessary mutable keyword

* Changed split-column to solt column after rebase from upstream

crates/nu-cli/tests/commands/sort_by.rs

@@ -22,6 +22,29 @@ fn by_column() {
     assert_eq!(actual.out, "description");
 }
 
+#[test]
+fn by_invalid_column() {
+    let actual = nu!(
+        cwd: "tests/fixtures/formats", pipeline(
+        r#"
+            open cargo_sample.toml --raw
+            | lines
+            | skip 1
+            | first 4
+            | split column "="
+            | sort-by ColumnThatDoesNotExist
+            | skip 1
+            | first 1
+            | get Column1
+            | trim
+            | echo $it
+        "#
+    ));
+
+    assert!(actual.err.contains("Can not find column to sort by"));
+    assert!(actual.err.contains("invalid column"));
+}
+
 #[test]
 fn sort_primitive_values() {
     let actual = nu!(