patch 9.0.0536: CI: codecov action update available

Problem:    CI: codecov action update available.
Solution:   Update Codecov 3.1.0 to 3.3.1. (closes #11188)
diff --git a/src/version.c b/src/version.c
index f7ef299..75611d1 100644
--- a/src/version.c
+++ b/src/version.c
@@ -700,6 +700,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    536,
+/**/
     535,
 /**/
     534,