patch 9.1.1088: tests: plugin tests are named inconsistently

Problem:  tests: plugin tests are named inconsistently
Solution: group them under a common 'plugin' prefix

related: #16599

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/version.c b/src/version.c
index 01ce873..7d50936 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1088,
+/**/
     1087,
 /**/
     1086,