Fix infratests

BUG=skia:

Change-Id: I19ff5750e12bbd66ba6c43fe8d6c3234f9bb1372
Reviewed-on: https://skia-review.googlesource.com/8132
Reviewed-by: Eric Boren <borenet@google.com>
diff --git a/infra/bots/tasks.json b/infra/bots/tasks.json
index 4d2d85b..ba5abbe 100644
--- a/infra/bots/tasks.json
+++ b/infra/bots/tasks.json
@@ -8222,7 +8222,7 @@
         {
           "name": "skia/bots/skimage",
           "path": "skimage",
-          "version": "version:20"
+          "version": "version:19"
         },
         {
           "name": "skia/bots/skp",
@@ -8270,7 +8270,7 @@
         {
           "name": "skia/bots/skimage",
           "path": "skimage",
-          "version": "version:20"
+          "version": "version:19"
         },
         {
           "name": "skia/bots/skp",
@@ -13255,7 +13255,7 @@
         {
           "name": "skia/bots/skimage",
           "path": "skimage",
-          "version": "version:20"
+          "version": "version:19"
         },
         {
           "name": "skia/bots/skp",