patch 8.2.0075: Python 3 unicode test still sometimes fails

Problem:    Python 3 unicode test still sometimes fails.
Solution:   Skip the test when 'termencoding' is not empty.
diff --git a/src/version.c b/src/version.c
index 30f4465..16544f7 100644
--- a/src/version.c
+++ b/src/version.c
@@ -743,6 +743,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    75,
+/**/
     74,
 /**/
     73,