patch 8.2.0156: various typos in source files and tests

Problem:    Various typos in source files and tests.
Solution:   Fix the typos. (Emir Sari, closes #5532)
diff --git a/src/normal.c b/src/normal.c
index c4963e6..512b799 100644
--- a/src/normal.c
+++ b/src/normal.c
@@ -5659,7 +5659,7 @@
     VIsual_reselect = TRUE;
 
     // Corner case: the 0 position in a tab may change when going into
-    // virtualedit.  Recalculate curwin->w_cursor to avoid bad hilighting.
+    // virtualedit.  Recalculate curwin->w_cursor to avoid bad highlighting.
     if (c == Ctrl_V && (ve_flags & VE_BLOCK) && gchar_cursor() == TAB)
     {
 	validate_virtcol();