vim-patch:9.1.0259: Normal mode TextChanged isn't tested properly (#28167)

Problem:  Normal mode TextChanged isn't tested properly.
Solution: Combine Test_Changed_ChangedI() and Test_Changed_ChangedI_2()
          and also run it on Windows. Fix a typo in main.c.
          (zeertzjq)

closes: vim/vim#14396

c422662933

src/nvim/state.c

@@ -289,7 +289,7 @@ static bool is_safe_now(void)
          && !debug_mode;
 }
 
-/// Trigger SafeState if currently in s safe state, that is "safe" is TRUE and
+/// Trigger SafeState if currently in a safe state, that is "safe" is true and
 /// there is no typeahead.
 void may_trigger_safestate(bool safe)
 {