fix: rename utf8 intraline regression test

Rename the regression test to test_utf8_intraline_diff_no_panic so it
 matches the PR description and stays easy to search when debugging similar
 UTF-8 intraline diff issues.

02-0033b485

Author: RandyMcMillan

tests/tests.rs

@@ -134,7 +134,7 @@ fn test_differ_restore() {
 }
 
 #[test]
-fn test_differ_compare_utf8() {
+fn test_utf8_intraline_diff_no_panic() {
     let first_text = vec!["\tcrab 🦀\n"];
     let second_text = vec!["\tcrab 🦞\n"];
     let differ = Differ::new();