Add missing color_config settings (#14603)

# Description

Fixes #14600 by adding a default value for missing keys in
`default_config.nu`:

* `$env.config.color_config.glob`
* `$env.config.color_config.closure`

# User-Facing Changes

Will no longer error when accessing these keys.

# Tests + Formatting

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

# After Submitting

N/A

crates/nu-utils/src/default_files/default_config.nu

@@ -20,6 +20,8 @@ $env.config.color_config = {
     row_index: green_bold
     record: white
     list: white
+    closure: green_bold
+    glob:cyan_bold
     block: white
     hints: dark_gray
     search_result: { bg: red fg: white }