Remove panics from random integer and make the constraint more idiomatic (#2578)

* Remove panics from random integer and make the constraint more idiomatic

* Add open intervals to NumericRange

crates/nu-cli/tests/commands/random/integer.rs

@@ -5,9 +5,33 @@ fn generates_an_integer() {
     let actual = nu!(
         cwd: ".", pipeline(
         r#"
-        random integer --min 42 --max 43
+        random integer 42..43
         "#
     ));
 
     assert!(actual.out.contains("42") || actual.out.contains("43"));
 }
+
+#[test]
+fn generates_55() {
+    let actual = nu!(
+        cwd: ".", pipeline(
+        r#"
+        random integer 55..55
+        "#
+    ));
+
+    assert!(actual.out.contains("55"));
+}
+
+#[test]
+fn generates_0() {
+    let actual = nu!(
+        cwd: ".", pipeline(
+        r#"
+        random integer ..<1
+        "#
+    ));
+
+    assert!(actual.out.contains("0"));
+}