patch 8.2.0507: getbufvar() may get the wrong dictionary

Problem:    Getbufvar() may get the wrong dictionary. (David le Blanc)
Solution:   Check for empty name. (closes #5878)
diff --git a/src/version.c b/src/version.c
index a53f44b..38ab531 100644
--- a/src/version.c
+++ b/src/version.c
@@ -739,6 +739,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    507,
+/**/
     506,
 /**/
     505,