patch 8.2.2830: terminal colors are not updated when 'background' is set

Problem:    Terminal colors are not updated when 'background' is set.
Solution:   Call term_update_colors() for all terminals. (Marcin Szamotulski,
            closes #8171, closes #8150)
diff --git a/src/optionstr.c b/src/optionstr.c
index 91d0a69..1ec8d05 100644
--- a/src/optionstr.c
+++ b/src/optionstr.c
@@ -908,6 +908,9 @@
 		init_highlight(FALSE, FALSE);
 	    }
 #endif
+#ifdef FEAT_TERMINAL
+	    term_update_colors_all();
+#endif
 	}
 	else
 	    errmsg = e_invarg;
@@ -2176,7 +2179,7 @@
     else if (varp == &curwin->w_p_wcr)
     {
 	if (curwin->w_buffer->b_term != NULL)
-	    term_update_colors();
+	    term_update_colors(curwin->w_buffer->b_term);
     }
 # if defined(MSWIN)
     // 'termwintype'