Rollup merge of #71020 - pyfisch:unicode-version, r=sfackler

Store UNICODE_VERSION as a tuple

Remove the UnicodeVersion struct containing
major, minor and update fields and replace it with
a 3-tuple containing the version number.
As the value of each field is limited to 255
use u8 to store them.

src/test/ui/char_unicode.rs

@@ -7,6 +7,6 @@ pub fn main() {
     check(std::char::UNICODE_VERSION);
 }
 
-pub fn check(unicode_version: std::char::UnicodeVersion) {
-    assert!(unicode_version.major >= 10);
+pub fn check(unicode_version: (u8, u8, u8)) {
+    assert!(unicode_version.0 >= 10);
 }