add 'from ndjson' into standard library (#10283)

close #8574
related #10276 
# Description

added below into standard library
```
def "from ndjson" []: string -> any {
    from json --objects
}
```

# User-Facing Changes


Users can use functions like "from ndjson" in standard library, and can
open ndjson files with `open` command.
```
use std formats *
# `from ndjson` is available now
open sample.ndjson
```

# Tests + Formatting

`toolkit check pr`

- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`


# After Submitting

---------

Co-authored-by: Stefan Holderbach <sholderbach@users.noreply.github.com>

crates/nu-std/src/lib.rs

@@ -28,6 +28,7 @@ pub fn load_standard_library(
             ("xml.nu", include_str!("../std/xml.nu")),
             ("input.nu", include_str!("../std/input.nu")),
             ("math.nu", include_str!("../std/math.nu")),
+            ("formats.nu", include_str!("../std/formats.nu")),
         ];
 
         let mut working_set = StateWorkingSet::new(engine_state);

crates/nu-std/std/formats.nu

@@ -0,0 +1,20 @@
+# formats.nu
+#
+# This file contains functions for formatting data in various ways.
+#
+# Usage:
+#   use std format *
+#   use std format <function name>
+#
+# These functions help `open` the files with unsupported extensions such as ndjson.
+#
+
+# Convert from ndjson to structured data.
+export def "from ndjson" []: string -> any {
+    from json --objects
+}
+
+# Convert from jsonl to structured data.
+export def "from jsonl" []: string -> any {
+    from json --objects
+}

crates/nu-std/tests/test_formats.nu

@@ -0,0 +1,54 @@
+use std assert
+
+def ndjson_test_data1 [] {
+  '{"a":1}
+{"a":2}
+{"a":3}
+{"a":4}
+{"a":5}
+{"a":6}'
+}
+
+#[test]
+def from_ndjson_multiple_objects [] {
+  use std formats *
+  let result = ndjson_test_data1 | from ndjson
+  let expect = [{a:1},{a:2},{a:3},{a:4},{a:5},{a:6}]
+  assert equal $result $expect "could not convert from NDJSON"
+}
+
+#[test]
+def from_ndjson_single_object [] {
+  use std formats *
+  let result = '{"a":1}' | from ndjson
+  let expect = [{a:1}]
+  assert equal $result $expect "could not convert from NDJSON"
+}
+
+#[test]
+def from_ndjson_invalid_object [] {
+  use std formats *
+  assert error { '{"a":1' | from ndjson }
+}
+
+#[test]
+def from_jsonl_multiple_objects [] {
+  use std formats *
+  let result = ndjson_test_data1 | from jsonl
+  let expect = [{a:1},{a:2},{a:3},{a:4},{a:5},{a:6}]
+  assert equal $result $expect "could not convert from JSONL"
+}
+
+#[test]
+def from_jsonl_single_object [] {
+  use std formats *
+  let result = '{"a":1}' | from jsonl
+  let expect = [{a:1}]
+  assert equal $result $expect "could not convert from JSONL"
+}
+
+#[test]
+def from_jsonl_invalid_object [] {
+  use std formats *
+  assert error { '{"a":1' | from jsonl }
+}