patch 9.0.0084: using "terraform" filetype for .tfvars file is bad

Problem:    Using "terraform" filetype for .tfvars file is bad.
Solution:   use "terraform-vars", so that different completion and other
            mechanisms can be used. (Radek Simko, closes #10755)
diff --git a/src/version.c b/src/version.c
index 7f4b42d..03b65d2 100644
--- a/src/version.c
+++ b/src/version.c
@@ -736,6 +736,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    84,
+/**/
     83,
 /**/
     82,