patch 8.0.0954: /proc/self/exe might be a relative path

Problem:    /proc/self/exe might be a relative path.
Solution:   Make the path a full path. (James McCoy, closes #1983)
diff --git a/src/version.c b/src/version.c
index 352e0a9..0990d83 100644
--- a/src/version.c
+++ b/src/version.c
@@ -770,6 +770,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    954,
+/**/
     953,
 /**/
     952,